Structurally-colored articles and methods for making and using structurally-colored articles

ABSTRACT

As described above, one or more aspects of the present disclosure provide articles having structural color, and methods of making articles having structural color. The surface of the article can include the optical element with sections that have different relative thicknesses from one another. A first section imparts a first structural color and a second section imparts a second structural color. The first structural color and the second structural color differ from each other when viewed from the same angle of observation from a viewer having 20/20 visual acuity and normal color vision from a distance of about 1 meter from the article including the optical element.

CLAIM OF PRIORITY TO RELATED APPLICATION

This application claims the benefit of and priority to U.S. ProvisionalApplication Ser. No. 63/032,052, having the title “STRUCTURALLY-COLOREDARTICLES AND METHODS FOR MAKING AND USING STRUCTURALLY-COLOREDARTICLES”, filed on May 29, 2020, and to U.S. Provisional ApplicationSer. No. 63/032,061, having the title “STRUCTURALLY-COLORED ARTICLES ANDMETHODS FOR MAKING AND USING STRUCTURALLY-COLORED ARTICLES”, filed onMay 29, 2020, and to U.S. Provisional Application Ser. No. 63/032,064,having the title “STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKINGAND USING STRUCTURALLY-COLORED ARTICLES”, filed on May 29, 2020, and toU.S. Provisional Application Ser. No. 63/032,067, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on May 29, 2020, and to U.S.Provisional Application Ser. No. 63/032,076, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on May 29, 2020, and to U.S.Provisional Application Ser. No. 63/032,081, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on May 29, 2020, and to U.S.Provisional Application Ser. No. 63/032,084, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on May 29, 2020, and to U.S.Provisional Application Ser. No. 63/032,090, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on May 29, 2020, and to U.S.Provisional Application Ser. No. 63/052,143, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on Jul. 15, 2020, and to U.S.Provisional Application Ser. No. 63/052,135, having the title“STRUCTURALLY-COLORED ARTICLES AND METHODS FOR MAKING AND USINGSTRUCTURALLY-COLORED ARTICLES”, filed on Jul. 15, 2020.

BACKGROUND

Structural color is caused by the physical interaction of light with themicro- or nano-features of a surface and the bulk material as comparedto color derived from the presence of dyes or pigments that absorb orreflect specific wavelengths of light based on the chemical propertiesof the dyes or pigments. Color from dyes and pigments can be problematicin a number of ways. For example, dyes and pigments and their associatedchemistries for fabrication and incorporation into finished goods maynot be environmentally friendly.

BRIEF DESCRIPTION OF THE DRAWINGS

Further embodiments of the present disclosure will be more readilyappreciated upon review of the detailed description of its variousembodiments, described below, when taken in conjunction with theaccompanying drawings.

FIGS. 1A-1M shows various articles of footwear, apparel, athleticequipment, container, electronic equipment, and vision wear that includethe primer layer in accordance with the present disclosure, while FIGS.1N(a)-1Q(e) illustrate additional details regarding different types offootwear.

FIGS. 2A and 2B are cross-section illustrations of optical elementshaving a textured surface and a substantially flat surface,respectively.

FIG. 3 illustrates an article including an optical element.

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

DESCRIPTION

The present disclosure provides for articles that exhibit structuralcolors through the use of an optical element having one or more layers.Structural colors (“single-hued” or “multi-hued” or “multi-hued withfull iridescence” or “multi-hued with limited iridescence”) are visiblecolors produced, at least in part, through optical effects (e.g.,through scattering, refraction, reflection, interference, and/ordiffraction of visible wavelengths of light). The structural colorproduced can be characterized based on the color parameters of the color(e.g., its hue, value, chroma, color space coordinates, iridescence type(limited or full), or any combination thereof) as determined at a singleangle of observation, as well as whether or not the properties of thecolor shift as the angle of observation shifts. The present disclosureprovides for single-hued structural colors (colors which do not shiftbetween hues as the angle of observation changes) as well as multi-huedstructural colors (e.g., multi-hued structural color, multi-huedstructural color with limited iridescence, and multi-hued structuralcolor with full iridescence). The structural colors can exhibit noiridescence (e.g., single-hued structural colors), multi-hued structuralcolor (e.g., appears to shift between hues), or can exhibit limitediridescence, or can exhibit full iridescence by shifting between all ornearly all the hues of visible light when viewed at different angles ofobservation. The methods and optical elements described herein can beused to impart two or more different colors to an article. Unlikeconventional pigment or dye-based methods, which use different type ofcolorants and/or different concentrations of colorants to impartdifferent colors to an article, the optical elements described hereincan be formed using a single process and a single set of raw materials,while producing an optical element having a layered structure thatproduces structural color which varies across the surface of thearticle. This variation in the layered structure of the optical elementimparts a variety of different structural colors to different regions ofa surface of an article.

The article includes the optical element (e.g., a single layerreflector, a single layer filter, a multilayer reflector or a multilayerfilter) including one or more layers (e.g., a reflective layer(s), aconstituent layer(s), and the like). The surface of the article caninclude the optical element with sections that have different relativethicknesses from one another. For example, a first section of theoptical element can have a first average thickness and a second sectioncan have a second average thickness, where the first average thicknessis different than the second average thickness. The first section andthe second section include a different number of layers but have atleast one corresponding layer that spans across the first section andthe second section. The average thickness of each corresponding layer inthe first section and the second section are the same. The first sectionimparts a first structural color (e.g., characterized by a colorparameter such as a hue, value, chroma, color space coordinates,iridescence type (limited or full), or any combination thereof) and thesecond section imparts a second structural color (e.g., characterized bya color parameter such as a hue, value, chroma, color space coordinates,iridescence type (limited or full), or any combination thereof). Thefirst structural color and the second structural color differ (e.g.,differ in at least one color parameter such as hue, value, chroma, colorsystem coordinates, type of iridescence, or any combination thereof, ordiffer in at least one of hue, value and chroma, or differ in hue) fromeach other when viewed from the same angle of observation orillumination, for example, by a viewer having 20/20 visual acuity andnormal color vision from a distance of about 1 meter from the articleincluding the optical element. In this way, with the different sectionsof the optical element producing different colors when viewed from thesame observation angle, the different sections of the optical element onthe article produce a patterned or random design on the article. In thismanner, an aesthetically pleasing and unique appearance is achieved as aresult of the multiple different structural colors, avoiding the need touse multiple pigments or dyes, or multiple coloration processes.

A variety of methods can be used to vary the thickness of a layer of theoptical element. In one example, when using a deposition method to formthe layer, depending upon the positioning of the article relative to thesource emitting the material forming the layer, the layer can bedeposited unevenly across the surface. Differences in relative heightsof elements on or above the surface, including elements of the surfaceor masks or both, can cast shadows on one or more sections of thesurface during the deposition process, creating variability in thethickness of one or more layers In another example, a mask can be usedto cover one or more sections of the surface during the depositionprocess, creating variability in the thickness of one or more layers.When using a deposition method, the materials being deposited can beattracted to sections of the article for example by using a magnet,and/or the materials being deposited can be repelled from sections ofthe article for example by using a gas, in order to vary the thicknessof a layer. One or more of this variety of methods can be used to varythe thickness of one or more layers within a single optical element.

The methods and optical elements described herein can be used to imparttwo or more different colors (e.g., differ in at least one colorparameter such as hue, value, chroma, color system coordinates, type ofiridescence, or any combination thereof, or differ in at least one ofhue, value and chroma, or differ in hue) to an article. The structuralcolor (e.g., the first and second structural color) can be producedsolely from the optical element without dyes and/or pigments.

The optical element includes at least one layer (e.g., constituentlayer, reflective layer), where the number of layer(s) of the firstsection and the second section are the different but the averagethickness of the corresponding layers is the same. Each layer can be adifferent thickness relative to vertically adjacent layers or can havethe same thickness. The combination of a different number of layerswhere the corresponding layers have the same thickness can contribute tothe difference (e.g., differ in at least one color parameter such ashue, value, chroma, color system coordinates, type of iridescence, orany combination thereof, or differ in at least one of hue, value andchroma, or differ in hue) in the first structural color (e.g.,characterized by a color parameter, such as a hue, value or chroma) andthe second structural color (e.g., characterized by a color parameter,such as a hue, value or chroma). Each corresponding layer in both thefirst section and the second section of the optical element consistessentially of the same material in both the first section and thesecond section of the optical element. Vertically adjacent layers can bemade of different materials. In addition, at least one layer in thefirst section and the second section form at least one correspondinglayer that extends over the first section of the optical element and thesecond section of the optical element.

In addition, the optical element can include an optional texturedsurface, where the optical element is disposed on a surface of thearticle with the optional textured surface between the optical elementand the surface or where the textured surface is part of the opticalelement, depending upon the design. The combination of the opticalelement and the optional textured surface imparts the first structuralcolor and/or the second structural color, to the article, where one orboth of the first and second structural colors can be designed to bedifferent than the color of the components of the optical element and/orthe underlying material, optionally with or without the application ofpigments or dyes to the article. In this way, the structural colors canimpart an aesthetically appealing color to the article without requiringthe use of inks or pigments and the environmental impact associated withtheir use.

In this way, the structural colors can impart an aesthetically appealingpatterned or random design to the article without requiring the use ofinks or pigments and the environmental impact associated with their use,although the structural colors optionally can be modified by theapplication of pigments or dyes to the article.

After disposing the optical element onto the article, the articleexhibits a different color from the underlying surface of the article.For example, the structural color can differ from the color of theunderlying surface of the article based on a color parameter such ashue, value, chroma, color space coordinates, iridescence type (limitedor full), or any combination thereof. In particular examples, thestructural colors themselves, and/or the structural color(s) and thecolor of the underlying surface of the article, differ from each otherin hue and/or iridescence type.

The article can be a finished article such as, for example, an articleof footwear, apparel or sporting equipment. The article can be acomponent of an article of footwear, apparel or sporting equipment, suchas, for example, an upper or a sole for an article of footwear, awaistband or arm or hood of an article of apparel, a brim of a hat, aportion of a backpack, or a panel of a soccer ball, and the like. Theoptical element can be disposed on the surface so that the reflectivelayer (as well as the other layers) is parallel or substantiallyparallel the surface (e.g., the plane of the reflective layer isparallel the plane of the surface of the article) (also referred to as“in-line”, or “in-line” configuration) or so that the reflective layeris perpendicular or substantially perpendicular the surface (alsoreferred to as the optical element laying “on its side”, or “on itsside” configuration).

The optical element can be disposed (e.g., affixed, attached, adhered,bonded, joined) on a surface of one or more components of the footwear,such as on the shoe upper and/or the sole. The optical element can beincorporated into the sole by incorporating it into a cushioning elementsuch as a bladder or a foam. The sole and/or upper can be designed sothat one or more portions of the structurally colored component arevisible in the finished article, by including an opening, or atransparent component covering the structurally colored component, andthe like.

In an aspect, the optical element can be disposed on a surface of apolymeric layer of the article, where the polymeric layer has a minimumpercent transmittance of 30 percent so that the structural color fromthe side facing the polymeric layer can be observed. In this way, theoptical element can be used to provide structural color through thepolymeric layer.

The present disclosure provides for an article comprising: an opticalelement disposed on a surface of the article, wherein the opticalelement includes at least a first section disposed on a first area ofthe article and a second section disposed on a second area of thearticle, wherein the first section of the optical element imparts afirst structural (e.g., characterized by a color parameter, such as ahue, value or chroma) color to the first area of the article, whereinthe second section of the optical element imparts a second structuralcolor (e.g., characterized by a color parameter, such as a hue, value orchroma) to the second area of the article, and the first structuralcolor and the second structural color are different when viewed from thesame angle of observation; wherein the optical element comprises atleast one layer, wherein the first section has a first number of layersand the second section has a second number of layers, wherein the firstnumber of layers and the second number of layer are different, whereinat least the first layer for each of the first section and the secondsection are made of the same material, wherein each of the layers of thesecond section have the same thickness of the corresponding layers inthe first section.

The present disclosure will be better understood upon reading thefollowing numbered aspects, which should not be confused with theclaims. Any of the numbered aspects below can, in some instances, can becombined with aspects described elsewhere in this disclosure and suchcombinations are intended to form part of the disclosure.

Aspect 1. An article comprising:

an optical element disposed on a surface of the article, wherein theoptical element includes at least a first section disposed on a firstarea of the article and a second section disposed on a second area ofthe article, wherein the first section of the optical element imparts afirst structural color (e.g., characterized by a hue, value, chroma,color space coordinates, iridescence type (limited or full), or anycombination thereof) to the first area of the article, wherein thesecond section of the optical element imparts a second structural color(e.g., characterized by a hue, value, chroma, color space coordinates,iridescence type (limited or full), or any combination thereof) to thesecond area of the article, and wherein the first structural color andthe second structural color are different (e.g., differ in at least onecolor parameter such as hue, value, chroma, color system coordinates,type of iridescence, or any combination thereof, or differ in at leastone of hue, value and chroma, or differ in hue) when viewed from thesame angle of observation by a person having 20/20 visual acuity andnormal color vision from a distance of about 1 meter from the articleunder the same lighting conditions;

wherein the optical element comprises at least one layer, wherein thefirst section has a first number of layers and the second section has asecond number of layers, wherein the first number of layers and thesecond number of layer are different, wherein at least the first layerfor each of the first section and the second section are made of thesame material, optionally wherein each of the layers of the secondsection have the same thickness of the corresponding layers in the firstsection.

Aspect 2. The article of any preceding aspect, wherein the first sectionhas a first layer having a first section first layer thickness and thesecond section has a first layer having a second section first layerthickness, wherein the first section first layer thickness and thesecond section first layer thickness are the same (optionally wherein atleast the second layer for each of the first section and the secondsection disposed on the first layer have the same thickness).Aspect 3. The article of any preceding aspect, wherein the first layerof the first section of the optical element and the first layer of thesecond section of the optical element form a first contiguous layerwhich extends over the first section of the optical element and thesecond section of the optical element (optionally, wherein each layer ofthe second section and each corresponding layer in the first sectioneach independently form a contiguous layer that which extends over thefirst section of the optical element and the second section of theoptical element).Aspect 4. The article of any preceding aspect, wherein the firstcontiguous layer consists essentially of the same material (optionallyeach contiguous layer independently consists essentially of the samematerial).Aspect 5. The article of any preceding aspect, wherein the first sectionincludes a first set of layers, wherein the second section includes asecond set of layers, wherein the first set of layers includes at leastone more layer than the second set of layers, wherein the material ofeach layer of the first set of layers corresponds to the material ofeach layer of the second set of layers, (optionally wherein verticallyadjacent layers of the second section are made of different materials,wherein vertically adjacent layers of the first section are made ofdifferent materials).Aspect 6. The article of any preceding aspect, wherein the first sectionincludes a first set of layers, wherein the second section includes asecond set of layers, wherein the index of refraction of eachcorresponding layer of the first set of layers corresponds to the indexof refraction of each corresponding layer of the second set of layers(optionally wherein vertically adjacent layers of the second sectionhave different index of refractions, wherein vertically adjacent layersof the first section have different index of refractions) (optionallywherein the index of refraction of each layer of the first set of layersis different, wherein the index of refraction of each layer of thesecond set of layers is different).Aspect 7. The article of any preceding aspect, wherein the second set oflayers is at least one (optionally 2-50 layers) layer less than thefirst set layers.Aspect 8. The article of any preceding aspect, wherein the surface ofthe article is a flat or a substantially flat surface, or wherein thesurface of the article is non-flat or not substantially non-flat.Aspect 9. A method of making an article, comprising: disposing theoptical element of any one of aspects 1 to 8 onto the surface of thearticle.Aspect 10. An article comprising: a product of the method of aspect 9.Aspect 11 The article or method of any one of the preceding aspects,wherein when measured according to the CIE 1976 color space under agiven illumination condition at a first observation angle of about −15to 180 degrees or about or about −15 degrees and +60 degrees, theoptical element has a first color measurement having coordinates L₁* anda₁* and b₁* as measured from the first section of the optical element,and optical element has a second color measurement having coordinatesL₂* and a₂* and b₂* as measured from the second section of the opticalelement, where ΔE*_(ab)=[(L₁*−L₂*)² (a₁*−a₂*)² (b₁*−b₂*)²]^(1/2),wherein the ΔE*_(ab) between the first color measurement and the secondcolor measurement is greater than about 2.2, or optionally the ΔE*_(ab)is greater than about 3, or optionally is greater than 4, or optionallyis greater than 5, the first structural color and the second structuralcolor are different.Aspect 12. The article or method of any one of the preceding aspects,wherein when measured according to the CIE 1976 color space under agiven illumination condition at a first observation angle of about −15to 180 degrees or about or about −15 degrees and +60 degrees, theoptical element has a first color measurement having coordinates L₁* anda₁* and b₁* as measured from the first section of the optical element,and optical element has a second color measurement having coordinatesL₂* and a₂* and b₂* as measured from the second section of the opticalelement, wherein the ΔE*_(ab) between the first color measurement andthe second color measurement is less than about 3, whereΔE*_(ab)=[(L₁*−L₂*)²+(a₁*−a₂*)²+(b₁*−b₂*)²]^(1/2), or optionally theΔE*_(ab) is less than about 2.2, the first structural color and thesecond structural color are the same or substantially the same.Aspect 13. The article or method of any one of the preceding aspects,wherein when measured according to the CIE 1976 color space under agiven illumination condition at a first observation angle of about −15to 180 degrees or about or about −15 degrees and +60 degrees, theoptical element has a first color measurement having coordinates L₁* anda₁* and b₁* as measured from the first section of the optical element,and optical element has a second color measurement having coordinatesL₂* and a₂* and b₂* as measured from the second section of the opticalelement, wherein the first structural color and the second structuralcolor are different structural colors when measured and assigned valuesin the L*a*b* system differ by at least 5 percent for at least one ofthe L*, a* or b* coordinates, or by at least 10 percent for at least oneof the L*, a* or b* coordinates.Aspect 14. The article or method of any one of the aspects, wherein theoptical element is on and visible from an outside surface of the articleor the optical element is on and visible from an inside surface of thearticle.Aspect 15. The article or method of any one of the preceding aspects,wherein the optical element is a single layer reflector, a single layerfilter, a multilayer reflector or a multilayer filter.Aspect 16. The article or method of any one of the preceding aspects,wherein the optical element includes at least one layer, optionallywherein the at least one layer includes at least one constituent layer,optionally wherein the at least one layer includes at least onereflective layer, optionally wherein the at least one layer includes atleast one constituent layer and at least one reflective layer.Aspect 17. The article or method of any one of the preceding aspects,wherein the optical element is an inorganic optical element, an organicoptical element, or a mixed inorganic/organic optical element.Aspect 18. The article or method of any one of the preceding aspects,wherein the organic optical element has at least one layer that is madeof an organic material, optionally wherein the at least one layer ismade of a non-metal or non-metal oxide material, optionally, wherein atleast one layer is made of a polymeric material (optionally a syntheticpolymeric material), optionally wherein the at least one layer is madean organic material that does not include a metal or metal oxide,optionally wherein the at least one layer is made of a polymeric(optionally a synthetic polymeric material) that does not include ametal or metal oxide.Aspect 19. The article or method of any one of the preceding aspects,wherein the optical element has 2 to 20 constituent layers and wherein,optionally, each constituent layer has a thickness of about one quarterof the wavelength of the wavelength to be reflected.Aspect 20. The article or method of any one of the preceding aspects,wherein each of the constituent layers have different refractiveindices.Aspect 21. The article or method of any one of the preceding aspects,each constituent layer has a thickness of at least 10 nanometers(optionally at least 30 nanometers, optionally at least 40 nanometers,optionally at least 50 nanometers, optionally at least 60 nanometers,optionally a thickness of from about 10 nanometers to about 100nanometers, or of from about 30 nanometers to about 80 nanometers, orfrom about 40 nanometers to about 60 nanometers).Aspect 22. The article or method of any of the preceding aspects,wherein the optical element has a thickness of about 100 to about 700nanometers, or of about 200 to about 500 nanometers.Aspect 23. The article or method of any one of the preceding aspects,wherein the at least one constituent layers is made of a materialselected from a metal or a metal oxide.Aspect 24. The article or method of any one of the aspects, wherein theat least one constituent layer is made of a metal.Aspect 25. The article or method of any one of the preceding aspects,wherein the metal is selected from the group consisting of: titanium,aluminum, silver, zirconium, chromium, magnesium, silicon, gold,platinum, and a combination thereof.Aspect 26. The article or method of any one of the preceding aspects,wherein at least one of the constituent layers comprises a metalselected from the group consisting of: titanium, aluminum, silver,zirconium, chromium, magnesium, silicon, gold, platinum, niobium, anoxide of any of these, and a combination thereof.Aspect 27. The article or method of any one of the preceding aspects,wherein at least one of the constituent layers is made of a materialselected from the group consisting of: silicon dioxide, titaniumdioxide, zinc sulphide, magnesium fluoride, tantalum pentoxide, and acombination thereof.Aspect 28. The methods and/or articles of any one of the precedingaspects, wherein the surface of the article is made of a material isselected from: thermoplastic polymer, thermoset polymer, elastomericpolymers, silicone polymers, natural and synthetic rubbers; compositematerials including polymers reinforced with carbon fiber and/or glass;natural leather; natural stone; porcelain materials; ceramic materials,metallic materials, glass materials, and combinations thereof.Aspect 29. The methods and/or articles of any one of the precedingaspects, wherein the thermoplastic material includes one or morethermoplastic polyurethanes, thermoplastic polyethers, thermoplasticpolyesters, thermoplastic polyamides, thermoplastic polyolefins,thermoplastic co-polymers thereof, or a combination thereof.Aspect 30. The methods and/or articles of any one of the precedingaspects, wherein the at least one constituent layer further comprises atextured surface, and the textured surface and the optical elementimparts the first structural color, the second structural color, orboth.Aspect 31. The methods and/or articles of any one of the precedingaspects, wherein the surface of the article is a textured surface,wherein the at least one constituent layer is on the textured surface,and the textured surface of the substrate and the optical element impartthe first structural color, the second structural color, or both.Aspect 32. The methods and/or articles of any one of the precedingaspects, wherein the textured surface includes a plurality of profilefeatures and flat planar areas, wherein the profile features extendabove the flat areas of the textured surface, optionally wherein thedimensions of the profile features, a shape of the profile features, aspacing among the plurality of the profile features, in combination withthe optical element create the first structural color, the secondstructural color, or both, optionally wherein the profile features arein random positions relative to one another for a specific area,optionally wherein the spacing among the profile features is set toreduce distortion effects of the profile features from interfering withone another in regard to the first structural color, the secondstructural color, or both of the article, optionally wherein the profilefeatures and the flat areas result in at least one layer of the opticalelement having an undulating topography across the textured surface,wherein there is a planar region between neighboring profile featuresthat is planar with the flat planar areas of the textured surface,wherein the planar region has dimensions relative to the profilefeatures to impart the first structural color, the second structuralcolor, or both, optionally wherein the profile features and the flatareas result in each layer of the optical element having an undulatingtopography across the textured surface.Aspect 33. The article and/or method of any of the preceding aspects,wherein the height of the profile feature is about 50 micrometers to 250micrometers, optionally wherein at least one of the length and width ofthe profile feature is less than 250 micrometers or both the length andthe width of the profile feature is less than 250 micrometers.Aspect 34. The article and/or method of any of the preceding aspects,wherein at least one of the dimensions of the profile feature is in thenanometer range, while at least one other dimension is in the micrometerrange.Aspect 35. The article and/or method of any of the preceding aspects,wherein the nanometer range is about 10 nanometers to about 1000nanometers, while the micrometer range is about 5 micrometers to 250micrometers.Aspect 36. The article and/or method of any of the preceding aspects,wherein at least one of the length and width of the profile feature isin the nanometer range, while the other of the length and the width ofthe profile feature is in the micrometer range.Aspect 37. The article and/or method of any of the preceding aspects,wherein at least one of the length and width of the profile feature isin the nanometer range and the other in the micrometer range, where theheight is about 250 nanometers to 250 micrometers.Aspect 38. The article and/or method of any of the preceding aspects,wherein spatial orientation of the profile features is periodic.Aspect 39. The article and/or method of any of the preceding aspects,wherein spatial orientation of the profile features is a semi-randompattern or a set pattern.Aspect 40. The article and/or method of any of the preceding aspects,wherein the surface of the layers of the optical element are asubstantially three dimensional flat planar surface or a threedimensional flat planar surface.Aspect 41. The methods and/or articles of any one of the precedingaspects, wherein the first structural color, the second structuralcolor, or both, independently, exhibits a single hue group or multipledifferent hue groups, or hues when viewed from different viewing anglesat least 15 degrees apart.Aspect 42. The methods and/or articles of any one of the precedingaspects, wherein the article is a fiber.Aspect 43. The methods and/or articles of any one of the precedingaspects, wherein the article is a yarn, optionally a monofilament yarn.Aspect 44. The methods and/or articles of any one of the precedingaspects, wherein the article is a rolled good.Aspect 45. The methods and/or articles of any one of the precedingaspects, wherein the article is a textile.Aspect 46. The methods and/or articles of any one of the precedingaspects, wherein the article is a knit textile.Aspect 47. The methods and/or articles of any one of the precedingaspects, wherein the article is a non-woven textile.Aspect 48. The methods and/or articles of any one of the precedingaspects, wherein the article is a synthetic leather.Aspect 49. The methods and/or articles of any one of the precedingaspects, wherein the article is a film.Aspect 50. The methods and/or articles of any one of the precedingaspects, wherein the article is an article of footwear, a component offootwear, an article of apparel, a component of apparel, an article ofsporting equipment, or a component of sporting equipment.Aspect 51. The methods and/or articles of any one of the precedingaspects, wherein the article is an article of footwear.Aspect 52. The methods and/or articles of any one of the precedingaspects, wherein the article is a sole component of an article offootwear.Aspect 52. The methods and/or articles of any one of the precedingaspects, wherein the article is foam midsole component of an article offootwear.Aspect 53. The methods and/or articles of any one of the precedingaspects, wherein the article is an upper component of an article offootwear.Aspect 54. The methods and/or articles of any one of the precedingaspects, wherein the article is a knit upper component of an article offootwear.Aspect 55. The methods and/or articles of any one of the precedingaspects, wherein the article is a non-woven synthetic leather upper foran article of footwear.Aspect 56. The methods and/or articles of any one of the precedingaspects, wherein the article is a bladder including a volume of a fluid,wherein the bladder has a first bladder wall having a first bladder wallthickness, wherein the first bladder wall has a gas transmission rate of15 cm³/m²·atm·day or less for nitrogen for an average wall thickness of20 mils.Aspect 57. The methods and/or articles of any one of the precedingaspects, wherein the article is a bladder, and the optical element isoptionally on an inside surface of the bladder or optionally the opticalelement is on an outside surface of the bladder.Aspect 58. The methods and/or articles of any preceding aspect, whereinthe first structural color, the second structural color, any combinationof two, independently, visible to a viewer having 20/20 visual acuityand normal color vision from a distance of about 1 meter from thebladder.Aspect 59. The methods and/or articles of any preceding aspect, whereinthe first structural color, the second structural color, and/or thethird structural color are multi-hued having full iridescence.Aspect 60. The methods and/or articles of any preceding aspect, whereinthe first structural color, the second structural color, and/or thethird structural color are multi-hued having limited iridescence.Aspect 61. The methods and/or articles of the preceding aspect, whereinthe first structural color, the second structural color, and/or thethird structural color are multi-hued having limited iridescence suchthat, when a hue of each of the structural colors imparted at the sameangle, or wherein each color is visible at each possible angle ofobservation, and is, independently, assigned to a single hue selectedfrom the group consisting of the primary, secondary and tertiary colorson the red yellow blue (RYB) color wheel, all of the assigned hues fallinto a single hue group, and the single hue group includes at least twohues (optionally at least three hues) selected from red, red-orange,orange, orange-yellow, yellow, yellow-green, green, green-blue, blue,blue-purple, purple, and purple-red.Aspect 62. The methods and/or articles of Aspect 61, wherein, in thesingle hue group, the hue of at least two of the first structural color,the second structural color, and the third structural color are directlyadjacent to the other two hues on the RYB color wheel (the hues includetwo analogous hues), optionally wherein the hues of all three structuralcolors are directly adjacent to each other on the RYB color wheel (allthree hues are analogous).Aspect 63. The methods and/or articles of Aspect 61, wherein the singlehue group is one of a) red and red-orange; b) red-orange and orange; c)orange and orange-yellow; d) orange-yellow and yellow; e) yellow andyellow-green; f) yellow-green and green; g) green and green-blue; h)green-blue and blue; i) blue and blue-purple; j) blue-purple and purple;k) purple and purple-red; and l) purple-red and red.Aspect 64. The methods and/or articles of Aspect 61, wherein the singlehue group is one of a) yellow-green, yellow, and orange-yellow; b)yellow, orange-yellow, and orange; c) orange-yellow, orange, andred-orange; d) red-orange, red, and purple-red; e) red, purple-red, andpurple; f) red-purple, purple, and blue-purple; g) purple, blue-purple,and blue; h) blue-purple, blue, and green-blue; i) blue, green-blue, andgreen; and j) green-blue, green, and yellow-green.Aspect 65. The methods and/or articles of Aspect 61, wherein, in thesingle hue group, the hue of at least two of the first structural color,the second structural color, and the third structural color are notdirectly adjacent to the others hues on the RYB color wheel (at leasttwo of the hues are non-analogous), optionally wherein the hues of allthree of the first structural color, the second structural color, andthe third structural color are not directly adjacent to each other onthe RYB color wheel (all three hues are non-analogous).Aspect 66. The methods and/or articles of Aspect 61, wherein the singlehue group is one of a) red and orange; b) red-orange and orange-yellow;c) yellow and green; d) yellow-green and green-blue; e) green and blue;f) green-blue and blue-purple; g) blue and purple; h) blue-purple andpurple-red; i) purple and red; and j) purple-red and red-orange.Aspect 67. The methods and/or articles of Aspect 61, wherein the singlehue group is one of a) red and orange-yellow; b) red-orange and yellow;c) orange and yellow-green; d) yellow-orange and green; e) yellow andgreen-blue; f) yellow-green and blue; g) green and blue-purple; h)green-blue and purple; i) blue and purple-red; j) blue-purple and red;k) purple and red-orange; and l) purple-red and orange.Aspect 68. The methods and/or articles of Aspect 61, wherein the singlehue group is one of a) red and yellow; b) red-orange and yellow-green;c) orange and green; d) orange-yellow and green-blue; e) yellow andblue; f) yellow-green and blue-purple; g) green and purple; h)green-blue and purple-red; i) blue and red; j) blue-purple andred-orange; k) purple and orange; and l) purple-red and orange-yellow.Aspect 69. The methods and/or articles of Aspect 61, wherein the singlehue group is one of a) red and yellow-green; b) red-orange and green; c)orange and green-blue; d) orange-yellow and blue; e) yellow andblue-purple; f) yellow-green and purple; g) green and purple-red; h)green-blue and red; i) blue and red-orange; j) blue-purple and orange,k) purple and orange-yellow, and l) purple-red and yellow.Aspect 70. The methods and/or articles of Aspect 61, wherein the singlehue group includes a complementary pair of hues, optionally wherein thecomplementary pair of hues includes a) red and green; b) red-orange andgreen-blue; c) orange and blue; d) orange-yellow and blue-purple; e)yellow and purple; and f) yellow-green and purple-red.Aspect 71. The methods and/or articles of the preceding aspect, whereinat least one of the first structural color, the second structural color,and the third structural color is an achromatic color, optionallywherein the achromatic color is black, gray or white.

Now having described embodiments of the present disclosure generally,additional discussion regarding embodiments will be described in greaterdetails.

This disclosure is not limited to particular embodiments described, andas such may, of course, vary. The terminology used herein serves thepurpose of describing particular embodiments only, and is not intendedto be limiting, since the scope of the present disclosure will belimited only by the appended claims.

Where a range of values is provided, each intervening value, to thetenth of the unit of the lower limit unless the context clearly dictatesotherwise, between the upper and lower limit of that range and any otherstated or intervening value in that stated range, is encompassed withinthe disclosure. The upper and lower limits of these smaller ranges mayindependently be included in the smaller ranges and are also encompassedwithin the disclosure, subject to any specifically excluded limit in thestated range. Where the stated range includes one or both of the limits,ranges excluding either or both of those included limits are alsoincluded in the disclosure.

As will be apparent to those of skill in the art upon reading thisdisclosure, each of the individual embodiments described and illustratedherein has discrete components and features which may be readilyseparated from or combined with the features of any of the other severalembodiments without departing from the scope or spirit of the presentdisclosure. Any recited method may be carried out in the order of eventsrecited or in any other order that is logically possible.

Embodiments of the present disclosure will employ, unless otherwiseindicated, techniques of material science, chemistry, textiles, polymerchemistry, and the like, which are within the skill of the art. Suchtechniques are explained fully in the literature.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art of material science, chemistry, textiles, polymer chemistry, andthe like. Although methods and materials similar or equivalent to thosedescribed herein can be used in the practice or testing of the presentdisclosure, suitable methods and materials are described herein.

As used in the specification and the appended claims, the singular forms“a,” “an,” and “the” may include plural referents unless the contextclearly dictates otherwise. Thus, for example, reference to “a support”includes a plurality of supports. In this specification and in theclaims that follow, reference will be made to a number of terms thatshall be defined to have the following meanings unless a contraryintention is apparent.

The present disclosure provides for articles (e.g., structurally colorarticles) that exhibit different structural colors (e.g., differ in atleast one color parameter such as hue, value, chroma, color systemcoordinates, type of iridescence, or any combination thereof, or differin at least one of hue, value and chroma, or differ in hue) in differentareas of the article using an optical element, where the optical elementhas a different thickness in at least two of those areas. The opticalelement (e.g., a single layer reflector, a single layer filter, amultilayer reflector or a multilayer filter) is disposed on the articleand has different heights in two or more sections due to the differentnumber of layers in each section of the optical element. Each sectionhas a corresponding structural color, where the structural color isvisible color produced, at least in part, through optical effects suchas through scattering, refraction, reflection, interference, and/ordiffraction of visible wavelengths of light. The structural color fromeach section can be a single color, multicolor, or iridescent, angle ofobservation dependent or angle of observation independent. In this way,articles including the optical element can provide for appealing visualcolors that can be patterned or random. The optical element can beincorporated onto one or more components of an article, for example,when the article is an article of footwear, on an upper or sole of anarticle of footwear.

The optical element includes at least one layer (e.g., constituentlayer, reflective layer), where the number of layer(s) of the firstsection and the second section are different (e.g., different by one ormore layers). For example, in the first section the optical element hasfour layers while in the second section the optical element incudesseven layers. The average thickness of the corresponding layers of thefirst section and the second section is the same. In addition, one ormore layers in the first section and the second section form one or morecorresponding layers (contiguous layers) that each extends over thefirst section and the second section so that the corresponding layer(s)is continuous. The different dimensions of each section can contributeto the difference (e.g., differ in at least one color parameter such ashue, value, chroma, color system coordinates, type of iridescence, orany combination thereof, or differ in at least one of hue, value andchroma, or differ in hue) in the first structural (e.g., characterizedby a color parameter such as a hue, value, chroma, color spacecoordinates, iridescence type (limited or full), or any combinationthereof) color and the second structural color (e.g., characterized by acolor parameter such as a hue, value, chroma, color space coordinates,iridescence type (limited or full), or any combination thereof). Inregard to the phrase “corresponding layer”, this phrase references alayer that was formed at the same time for each section (e.g., firstlayer of the first section and the first layer of the second section arecorresponding layers; the third layer of the first section and the thirdlayer of the second section are corresponding layers; and so on). Thephrase “non-corresponding layer” refers to one or more layers that areformed at a different time and/or using a technique (e.g., mask) thatallows formation of the layer in one section of the optical element andnot in another section of the optical element. While reference is madeto two sections (e.g., first section, second section), a plurality ofsections is contemplated and can include 10s to 100s to 1000s or moredepending upon the article and the desired effect.

Generally, the optical element can include one or more layers (e.g.,constituent layers, reflective layers). Also as described herein, theoptical element can optionally include a textured surface, such as atextured layer and/or a textured structure. Optionally, the opticalelement can include one or more layers (e.g., protection layer, and thelike) to provide one or more characteristics to the optical element(e.g., better wear characteristic, better adhesion characteristic, andthe like).

The optical element can be disposed on a surface in a variety of ways.For example, the optical element can be disposed on the surface so thateach of the layers of the optical element are parallel or substantiallyparallel the surface (e.g., disposed “in line”). In other words, thelength and width of the layers of the optical element define the plane,while the thickness of the layer is the smallest dimension. In anotherexample, each of the layers of the optical element are perpendicular orsubstantially perpendicular the surface. In either configuration, theoptical element can produce an aesthetically pleasing appearance.

In one or more embodiments of the present disclosure the surface of thearticle includes the optical element, and is optionally a texturedsurface, where the optical element and optionally the textured surfaceimpart structural color (e.g., single-hued or multi-hued). The optionaltextured surface can be disposed between the optical element and thesurface or be part of the optical element, depending upon the design.Additional details are provided herein.

In an embodiment, the structural color (e.g. the first structural color,the second structural color, third structural color . . . the fifthstructural color and so on) is not used in combination with a pigmentand/or dye. In other words, the structural color is derived from theoptical element solely. In another aspect, the structural color can beused in combination with a pigment and/or dye, but the structural coloris not the same hue, value, chroma, or any combination of a hue, a valueand a chroma as the pigment and/or dye, meaning that the structuralcolor alone, and the structural color in combination with the pigmentand/or dye differ from each other in at least one color property orcharacteristic (e.g., hue, value, chroma, color space coordinate,iridescence type, etc.). In this regard, the structural color is theproduct of the textured surface, the optical element, and/or the pigmentand/or dye. In an embodiment, the structural color can be used incombination with a pigment and/or dye to enhance the color of thepigment and/or dye in regard to the color of the pigment and/or dye orenhance a hue, value, chroma or other color property associated with thepigment and/or dye. In an aspect, the structural color is impartedsolely by the layers of the optical element and not by pigments and/ordyes. In an aspect, the structural color is imparted solely by thelayers of the optical element and not by the textured surface. In anaspect, the structural color is imparted solely by the layers of theoptical element and not by pigments and/or dyes or the textured surface.

The article can be an article of manufacture or a component of thearticle. The article of manufacture can include footwear, apparel (e.g.,shirts, jerseys, pants, shorts, gloves, glasses, socks, hats, caps,jackets, undergarments), containers (e.g., backpacks, bags), andupholstery for furniture (e.g., chairs, couches, car seats), bedcoverings (e.g., sheets, blankets), table coverings, towels, flags,tents, sails, and parachutes, or components of any one of these. Inaddition, the optical element can be used with or disposed on textilesor other items such as striking devices (e.g., bats, rackets, sticks,mallets, golf clubs, paddles, etc.), athletic equipment (e.g., golfbags, baseball and football gloves, soccer ball restriction structures),protective equipment (e.g., pads, helmets, guards, visors, masks,goggles, etc.), locomotive equipment (e.g., bicycles, motorcycles,skateboards, cars, trucks, boats, surfboards, skis, snowboards, etc.),balls or pucks for use in various sports, fishing or hunting equipment,furniture, electronic equipment, construction materials, eyewear,timepieces, jewelry, and the like.

The surface of the article can be a flat or a substantially flat surface(e.g., can include topographical features that are less than about 1millimeter). The surface of the article can be non-flat or notsubstantially non-flat (e.g., include topographical features (e.g.,random or patterned) greater than about 1 millimeter that do notcontribute to imparting optical color).

The article can be an article of footwear. The article of footwear canbe designed for a variety of uses, such as sporting, athletic, military,work-related, recreational, or casual use. Primarily, the article offootwear is intended for outdoor use on unpaved surfaces (in part or inwhole), such as on a ground surface including one or more of grass,turf, gravel, sand, dirt, clay, mud, pavement, and the like, whether asan athletic performance surface or as a general outdoor surface.However, the article of footwear may also be desirable for indoorapplications, such as indoor sports including dirt playing surfaces forexample (e.g., indoor baseball fields with dirt infields).

In particular, the article of footwear can be designed for use in indooror outdoor sporting activities, such as global football/soccer, golf,American football, rugby, baseball, running, track and field, cycling(e.g., road cycling and mountain biking), and the like. The article offootwear can optionally include traction elements (e.g., lugs, cleats,studs, and spikes as well as tread patterns) to provide traction on softand slippery surfaces, where components of the present disclosure can beused or applied between or among the traction elements and optionally onthe sides of the traction elements but on the surface of the tractionelement that contacts the ground or surface. Cleats, studs and spikesare commonly included in footwear designed for use in sports such asglobal football/soccer, golf, American football, rugby, baseball, andthe like, which are frequently played on unpaved surfaces. Lugs and/orexaggerated tread patterns are commonly included in footwear includingboots design for use under rugged outdoor conditions, such as trailrunning, hiking, and military use.

In particular, the article can be an article of apparel (i.e., agarment). The article of apparel can be an article of apparel designedfor athletic or leisure activities. The article of apparel can be anarticle of apparel designed to provide protection from the elements(e.g., wind and/or rain), or from impacts.

In particular, the article can be an article of sporting equipment. Thearticle of sporting equipment can be designed for use in indoor oroutdoor sporting activities, such as global football/soccer, golf,American football, rugby, baseball, running, track and field, cycling(e.g., road cycling and mountain biking), and the like.

FIGS. 1A-1M illustrates footwear, apparel, athletic equipment,container, electronic equipment, and vision wear that include thestructure (e.g., the optical element, optionally the textured surface)of the present disclosure. The structure can include the optical elementin the “in-line” configuration and/or the “on its side” configuration.The structure including the optical element is represented by hashedareas 12A′/12M′-12A″/12M′. The location of the structure is providedonly to indicate one possible area that the structure can be located.Also, two locations are illustrated in some of the figures and onelocation is illustrated in other figures, but this is done only forillustration purposes as the items can include one or a plurality ofstructure, where the size and location can be determined based on theitem. The structure(s) located on each item can represent a number,letter, symbol, design, emblem, graphic mark, icon, logo, or the like.

FIGS. 1N(a) and 1N(b) illustrate a perspective view and a side view ofan article of footwear 100 that include a sole structure 104 and anupper 102. The structure including the optical element is represented by122 a and 122 b. The sole structure 104 is secured to the upper 102 andextends between the foot and the ground when the article of footwear 100is worn. The primary elements of the sole structure 104 are a midsole114 and an outsole 112. The midsole 114 is secured to a lower area ofthe upper 102 and may be formed of a polymer foam or another appropriatematerial. In other configurations, the midsole 114 can incorporatefluid-filled chambers, plates, moderators, and/or other elements thatfurther attenuate forces, enhance stability, or influence motions of thefoot. The outsole 112 is secured to a lower surface of the midsole 114and may be formed from a wear-resistant rubber material that is texturedto impart traction, for example. The upper 102 can be formed fromvarious elements (e.g., lace, tongue, collar) that combine to provide astructure for securely and comfortably receiving a foot. Although theconfiguration of the upper 102 may vary significantly, the variouselements generally define a void within the upper 102 for receiving andsecuring the foot relative to sole structure 104. Surfaces of the voidwithin upper 102 are shaped to accommodate the foot and can extend overthe instep and toe areas of the foot, along the medial and lateral sidesof the foot, under the foot, and around the heel area of the foot. Theupper 102 can be made of one or more materials such as textiles, apolymer foam, leather, synthetic leather, and the like that are stitchedor bonded together. Although this configuration for the sole structure104 and the upper 102 provides an example of a sole structure that maybe used in connection with an upper, a variety of other conventional ornonconventional configurations for the sole structure 104 and/or theupper 102 can also be utilized. Accordingly, the configuration andfeatures of the sole structure 104 and/or the upper 102 can varyconsiderably.

FIGS. 1O(a) and 1O(b) illustrate a perspective view and a side view ofan article of footwear 130 that include a sole structure 134 and anupper 132. The structure including the optical element is represented by136 a and 136 b/136 b′. The sole structure 134 is secured to the upper132 and extends between the foot and the ground when the article offootwear 130 is worn. The upper 132 can be formed from various elements(e.g., lace, tongue, collar) that combine to provide a structure forsecurely and comfortably receiving a foot. Although the configuration ofthe upper 132 may vary significantly, the various elements generallydefine a void within the upper 132 for receiving and securing the footrelative to the sole structure 134. Surfaces of the void within theupper 132 are shaped to accommodate the foot and can extend over theinstep and toe areas of the foot, along the medial and lateral sides ofthe foot, under the foot, and around the heel area of the foot. Theupper 132 can be made of one or more materials such as textilesincluding natural and synthetic leathers, molded polymeric components,polymer foam and the like that are stitched or bonded together.

The primary elements of the sole structure 134 are a forefoot component142, a heel component 144, and an outsole 146. Each of the forefootcomponent 142 and the heel component 144 are directly or indirectlysecured to a lower area of the upper 132 and formed from a polymermaterial that encloses a fluid, which may be a gas, liquid, or gel.During walking and running, for example, the forefoot component 142 andthe heel component 144 compress between the foot and the ground, therebyattenuating ground reaction forces. That is, the forefoot component 142and the heel component 144 are inflated and may be pressurized with thefluid to cushion the foot. The outsole 146 is secured to lower areas ofthe forefoot component 142 and the heel component 144 and may be formedfrom a wear-resistant rubber material that is textured to imparttraction. The forefoot component 142 can be made of one or more polymers(e.g., layers of one or more polymers films) that form a plurality ofchambers that includes a fluid such as a gas. The plurality of chamberscan be independent or fluidically interconnected. Similarly, the heelcomponent 144 can be made of one or more polymers (e.g., layers of oneor more polymers films) that form a plurality of chambers that includesa fluid such as a gas and can also be independent or fluidicallyinterconnected. In some configurations, the sole structure 134 mayinclude a foam layer, for example, that extends between the upper 132and one or both of the forefoot component 142 and the heel component144, or a foam element may be located within indentations in the lowerareas of the forefoot component 142 and the heel component 144. In otherconfigurations, the sole structure 132 may incorporate Oates,moderators, lasting elements, or motion control members that furtherattenuate forces, enhance stability, or influence the motions of thefoot, for example. Although the depicted configuration for the solestructure 134 and the upper 132 provides an example of a sole structurethat may be used in connection with an upper, a variety of otherconventional or nonconventional configurations for the sole structure134 and/or the upper 132 can also be utilized. Accordingly, theconfiguration and features of the sole structure 134 and/or the upper132 can vary considerably.

FIG. 1O(c) is a cross-sectional view of A-A that depicts the upper 132and the heel component 144. The optical element 136 b can be disposed onthe outside wall of the heel component 144 or alternatively oroptionally the optical element 136 b′ can be disposed on the inside wallof the heel component 144.

FIGS. 1P(a) and 1P(b) illustrate a perspective view and a side view ofan article of footwear 160 that includes traction elements 168. Thestructure including the optical element is represented by 172 a and 172b. The article of footwear 160 includes an upper 162 and a solestructure 164, where the upper 162 is secured to the sole structure 164.The sole structure 164 can include one or more of a toe plate 166 a, amid-plate 166 b, and a heel plate 166 c. The plate can include one ormore traction elements 168, or the traction elements can be applieddirectly to a ground-facing surface of the article of footwear. As shownin FIGS. 1P(a) and (b), the traction elements 168 are cleats, but thetraction elements can include lugs, cleats, studs, and spikes as well astread patterns to provide traction on soft and slippery surfaces. Ingeneral, the cleats, studs and spikes are commonly included in footweardesigned for use in sports such as global football/soccer, golf,American football, rugby, baseball, and the like, while lugs and/orexaggerated tread patterns are commonly included in footwear (not shown)including boots design for use under rugged outdoor conditions, such astrail running, hiking, and military use. The sole structure 164 issecured to the upper 162 and extends between the foot and the groundwhen the article of footwear 160 is worn. The upper 162 can be formedfrom various elements (e.g., lace, tongue, collar) that combine toprovide a structure for securely and comfortably receiving a foot.Although the configuration of the upper 162 may vary significantly, thevarious elements generally define a void within the upper 162 forreceiving and securing the foot relative, to the sole structure 164.Surfaces of the void within upper 162 are shaped to accommodate the footand extend over the instep and toe areas of the foot, along the medialand lateral sides of the foot, under the foot, and around the heel areaof the foot. The upper 162 can be made of one or more materials such astextiles including natural and synthetic leathers, molded polymericcomponents, a polymer foam, and the like that are stitched or bondedtogether. In other aspects not depicted, the sole structure 164 mayincorporate foam, one or more fluid-filled chambers, plates, moderators,or other elements that further attenuate forces, enhance stability, orinfluence the motions of the foot. Although the depicted configurationfor the sole structure 164 and the upper 162 provides an example of asole structure that may be used in connection with an upper, a varietyof other conventional or nonconventional configurations for the solestructure 164 and/or the upper 162 can also be utilized. Accordingly,the configuration and features of the sole, structure 164 and/or theupper 162 can vary considerably.

FIGS. 1Q(a)-1Q(e) illustrate additional views of exemplary articles ofathletic footwear including various configurations of upper 176. FIG.1Q(a) is an exploded perspective view of an exemplary article ofathletic, footwear showing insole 174, upper 176, optional midsole oroptional lasting board 177, and outsole 178, which can take the form ofa plate. Structures including optical elements are represented by 175a-175 d, FIG. 1Q(b) is a top view of an exemplary article of athleticfootwear indicating an opening 183 configured to receive a wearer's footas well as an ankle collar 181 which may include optical element 182.The ankle collar is configured to be positioned around a wearer's ankleduring wear, and optionally can include a cushioning element. Alsoillustrated are the lateral side 180 and medial side 179 of theexemplary article of athletic footwear. FIG. 1Q(c) is a back view of thearticle of footwear depicted in FIG. 1Q(b), showing an optional heelclip 184 that can include optical element 185. FIG. 1Q(d) shows a sideview of an exemplary article of athletic footwear, which may optionallyalso include a tongue 186, laces 188, a toe cap 189, a heel counter 190,a decorative element such as a logo 191, and/or eyestays for the laces192 as well as a toe area 193 a, a heel area 193 b, and a vamp 193 c. Insome aspects, the heel counter 190 can be covered by a layer of knitted,woven, or nonwoven fabric, natural or synthetic leather, film, or othershoe upper material. In some aspects, the eyestays 192 are formed as onecontinuous piece; however, they can also comprise several separatepieces or cables individually surrounding a single eyelet or a pluralityof eyelets. Structures including optical elements are represented by 187a-187 e. While not depicted, optical elements can be present on theeyestays 192 and/or the laces 188. In some configurations, the solestructure can include a sole structure, such as a midsole having acushioning element in part or substantially all of the midsole, and theoptical element can be disposed on an externally-facing side of the solestructure, including on an externally-facing side of the midsole. FIG.1Q(e) is a side view of another exemplary article of athletic footwear.In certain aspects, the upper can comprise one or more containmentelements 194 such as wires, cables or molded polymeric componentextending from the lace structure over portions of the medial andlateral sides of the exemplary article of athletic footwear to the topof the sole structure to provide lockdown of the foot to the solestructure, where the containment element(s) can have an optical element(not shown) disposed on an externally-facing side thereon. In someconfigurations, a rand (not shown) can be present across part or all ofthe biteline 195.

Now having described embodiments of the present disclosure generally,additional details are provided. As has been described herein, thestructural color can include one of a number of colors. The “color” ofan article as perceived by a viewer can differ from the actual color ofthe article, as the color perceived by a viewer is determined by theactual color of the article (e.g., the color of the light leaving thesurface of the article), by the presence of optical elements which mayabsorb, refract, interfere with, or otherwise alter light reflected bythe article, the viewer's visual acuity, by the viewer's ability todetect the wavelengths of light reflected by the article, by thecharacteristics of the perceiving eye and brain, by the intensity andtype of light used to illuminate the article (e.g., sunlight,incandescent light, fluorescent light, and the like), as well as otherfactors such as the coloration of the environment of the article. As aresult, the color of an object as perceived by a viewer can differ fromthe actual color of the article.

Conventionally, non-structural color is imparted to man-made objects byapplying colored materials such as pigments or dyes to the object.Non-structurally colored materials are made of molecules (e.g.,chromophores) that absorb all but particular wavelengths of light andreflect back the unabsorbed wavelengths, or which absorb and emitparticular wavelengths of light. In non-structural color, it is theunabsorbed and/or the emitted wavelengths of light which impart thecolor to the article. As the color-imparting property is due tomolecule's chemical structure, the only way to remove or eliminate thecolor is to remove the molecules or alter their chemical structure.

While “structural color” is found in nature, more recently, methods ofimparting “structural color” to man-made objects have been developed.Structural color is color that is produced, at least in part, bymicroscopically structured surfaces that interfere with visible lightcontacting the surface. The structural color is color caused by physicalstructures which produce optical phenomena including the scattering,refraction, reflection, interference, and/or diffraction of light. Insome aspects, structural color can be caused by one or more of theseoptical phenomena in combination with absorption or emission. Forexample, optical phenomena which impart structural color can includemultilayer interference, thin-film interference, refraction, dispersion,light scattering, including Mie scattering, and diffraction, includingdiffraction grating. As structural color is produced by physicalstructures, destroying or altering the physical structures can eliminateor alter the imparted color. The ability to eliminate color bydestroying the physical structure, such as by grinding or melting anarticle can facilitate recycling and reuse colored materials. In variousaspects described herein, the structural color imparted to a region ofan external surface of an article is visible to a viewer having 20/20visual acuity and normal color vision from a distance of about 1 meterfrom the article, when the structurally-colored region is illuminated byabout 30 lux of sunlight, incandescent light, or fluorescent light. Insome such aspects, the structurally-colored region is at least onesquare centimeter in size.

As described herein, structural color is produced, at least in part, bythe optical element, as opposed to the color being produced solely bypigments and/or dyes. The coloration of a structurally-colored articlecan be due solely to structural color (i.e., the article, a coloredportion of the article, or a colored outer layer of the article can besubstantially free of pigments and/or dyes). In another aspect, anoptical element can impart a “combined color,” where a “combined color”can be described as having a structural component and a non-structuralcolor component. For example, structural color can be used incombination with pigments and/or dyes to alter all or a portion of astructural color, forming a combined color. In a combined color, thestructural color component, when viewed without the non-structural colorcomponent, imparts a structural color having a first color and thenon-structural color component, when viewed without the structural colorcomponent imparts a second color, where the first color and the secondcolor differ in at least one of a color property or characteristic suchas hue, value, chroma, color space coordinate, iridescence type, etc.,or differ in hue or chroma. Further in this aspect, when viewedtogether, the first color and the second color combine to form a third,combined color, which differs in at least one color property orcharacteristic, or differ in hue and chroma from either the first coloror the second color, for example, through shifting the reflectancespectrum of the optical element.

In another aspect, an optical element can impart a “modified color,”where a “modified color” can be described as having a structural colorcomponent and a modifier component. In a modified color, the structuralcolor component, when viewed without the modifier component, imparts astructural color having a specific hue and/or chroma and the modifiercomponent, when viewed without the structural color component, does notimpart any color, hue, or chroma. Further in this aspect, when viewedtogether, the modifier component can expand, narrow, or shift the rangeof wavelengths of light reflected by the structural color component.

In still another aspect, an optical element can impart a “modifiedcombined color,” where a “modified combined color” can be described hashaving a structural color component having a first color, anon-structural color component having a second color, and a modifiercomponent not imparting a color but instead functioning to expand,narrow, or shift the range of wavelengths of light reflected by thecombined color formed from the structural color component and thenon-structural color component.

In one aspect, the structural color component, combined color component,or modified color component disclosed herein is opaque; that is, itprevents light from passing through any articles to which they areapplied. Further in this aspect, most wavelengths of light are absorbedby one or more layers of the structural color, combined color, ormodified color component, with only a narrow band of light reflectedabout the wavelength of maximum reflectance.

“Hue” is commonly used to describe the property of color which isdiscernible based on a dominant wavelength of visible light, and isoften described using terms such as magenta, orange, yellow, green,cyan, blue, indigo, violet, etc. or can be described in relation (e.g.,as similar or dissimilar) to one of these. The hue of a color isgenerally considered to be independent of the intensity or lightness ofthe color. For example, in the Munsell color system, the properties ofcolor include hue, value (lightness) and chroma (color purity).Particular hues are commonly associated with particular ranges ofwavelengths in the visible spectrum: the range of about 750 to 635nanometers is associated with red, the range of about 635 to 590nanometers is associated with orange, the range of about 590 to 560nanometers is associated with yellow, the range of about 560 to 520nanometers is associated with green, the range of about 520 to 490nanometers is associated with cyan, the range of about 490 nanometers to450 nanometers is associated with blue, and the range of about 450 to400 nanometers is associated with violet.

In various aspects described herein, the hue or hues of the structuralcolor imparted to a region of an external surface of an article isvisible to a viewer having 20/20 visual acuity and normal color visionfrom a distance of about 1 meter from the article, when thestructurally-colored region is illuminated by about 30 lux of sunlight,incandescent light, or fluorescent light. Similarly, a viewer having20/20 visual acuity and normal color vision, when viewing twostructurally-colored regions under these conditions, where either bothregions are on the same article, or the two regions are individually ondifferent articles, can determine whether or not the hues imparted tothe two regions are the same or different. Further, a viewer having20/20 visual acuity and normal color vision, when viewing onestructurally-colored region under these conditions but at two differentviewing angles, can determine whether or not the hues imparted to theregion are the same or different.

When used in the context of structural color, one can characterize thehue of a structurally-colored article, i.e., an article that has beenstructurally colored by incorporating an optical element into thearticle, based on the wavelengths of light the structurally-coloredportion of the article absorbs and reflects (e.g., linearly andnon-linearly). While the optical element may impart a first structuralcolor, the presence of an optional textured surface and/or primer layercan alter the structural color. Other factors such as coatings ortransparent elements may further alter the perceived structural color.The hue of the structurally colored article can include any of the huesdescribed herein as well as any other hues or combination of hues.

The structural color can be referred to as a “single-hued” or“multi-hued” or “multi-hued with full iridescence” or “multi-hued withlimited iridescence”.

As used herein, single-hued structural color refers to a structuralcolor in which the hue of the structural color does not vary (e.g., doesnot appear to shift between hues), or does not vary substantially (e.g.,varies by about 10 percent or less, or by about 5 percent or less, or byabout 1 percent or less) when the angle of observation or illuminationis varied between or among two or more different angles that are atleast 15 degrees apart from each other (such as from 30 degrees to 45degrees, from 45 degrees to 60 degrees, from 60 degrees to 75 degrees,and so on). In this way, the hue of a single-hued structural color canbe described as being angle-independent, and a single-hued color isunderstood not to be iridescent or have a limited or full iridescence asdescribed herein. A number of different color names, color systems andcolor wheels can be used to describe hues. The value (degree oflightness), or the chroma (the purity of the hue), or both the value andthe chroma of a single-hued structural color can be angle dependent orcan be angle independent. For example, the structural color can be asingle-hued angle independent structural color in which the value andchroma of the single hue does not vary or does not vary substantially asthe angle of observation or illumination is varied. Alternatively, thestructural color can be a single-hued angle independent structural colorin which the value, the chroma, or both the value and the chroma variesor varies substantially as the angle of observation or illumination isvaried.

As used herein, multi-hued structural color refers to a structural colorin which the hue of the structural color varies (e.g., appears to shiftbetween hues) or varies substantially (e.g., varies by about 90 percent,about 95 percent, or about 99 percent) as the angle of observation orillumination is varied between or among two or more different anglesthat are at least 15 degrees apart from each other (such as from 30degrees to 45 degrees, from 45 degrees to 60 degrees, from 60 degrees to75 degrees, and so on). In this way, a multi-hued structural color canbe described as being angle-dependent, and a multi-hued structural coloris understood to be iridescent or have limited or full iridescence, asdescribed here. For example, a multi-hued structural color can display adifferent hue (e.g., as the angle of observation or illumination isvaried, the imparted hue changes between/among 2, 3, 4, 5, 6 or moredistinct hues). Each of the individual hues exhibited by the multi-huedstructural color can be a primary color such as magenta, yellow or cyan,or red, yellow or blue, or can be a secondary hue such as orange, greenor purple, or can be a tertiary hue such as red-orange or orange-red.The value, chroma or both the value and chroma of an individual hueexhibited by the multi-hued structural color can be angle dependent,meaning that the value, the chroma or both the value and the chroma ofthe individual hue varies as the angle of observation or illuminationvaries. The value, chroma or both the value and the chroma of theindividual hue exhibited by the multi-hued structural can be angleindependent, meaning that-the value, the chroma, or both the value andchroma of the individual hue do not vary or do not vary substantially asthe angle of observation or illumination is varied.

Multi-hued structural colors can be classified based on the type ofiridescence they display. A multi-hued structural color can be amulti-hued structural color with full iridescence, meaning that itappears to display all or virtually all the hues of visible light inorder (from shortest wavelength to longest wavelength, or from longestwavelength to shortest wavelength) as the angle of observation orillumination is varied, providing a “rainbow” effect. As used herein,multi-hued structural color with limited iridescence is understood torefer to multi-hued structural colors which vary between a limitednumber of individual hues (between 2 hues, 3 hues, or 4 distinct hues)as the angle of observation or illumination is varied between or amongtwo or more different angles that are at least 15 degrees apart fromeach other. Thus, multi-hued structural colors with limited iridescencedo not exhibit the “rainbow” effect, but instead exhibit only a few huesand is distinguishable from multi-hued structural color with fulliridescence and single-hued structural color.

The individual hues of the multiple hues exhibited by multi-huedstructural colors with limited iridescence can be adjacent to each otheron the color wheel (e.g., the multiple hues can include, and varybetween, blue and blue-purple, or among blue-green, blue, andblue-purple). Alternatively, the individual hues of the multiple huesexhibited by a multi-hued structural color with limited iridescence mayinclude hues which are not directly adjacent to each other on the colorwheel, such that some hues directly adjacent to the imparted hues on thecolor wheel are omitted or “skipped over” (e.g., the multiple impartedhues can include, and vary between, orange-red and yellow-green, or themultiple imparted hues can include orange-red, orange, andyellow-green). In a multi-hued structural color with limitediridescence, each individual hue of the limited number of multiple huesmay only be observed at a few angles (e.g., about 10 to 90 degrees orabout 10 to 120 degrees or about 10 to 60 degrees) of observation orillumination. For example, a first hue (e.g., blue) can be exhibited ata majority (e.g., about 1 to 300 degrees or about 1 to 200 degrees) ofangles of observation or illumination within a 360 degree radius, whilea second hue (e.g., blue-purple) or the second hue and/or a third hue(e.g., blue-green) can be exhibited at a minority (e.g., about 10 to 90degrees or about 10 to 120 degrees or about 10 to 60 degrees) of anglesof observation or illumination within the 360 degree radius. In anotherexample where the degree radius is less than 360 degrees, a first hue(e.g., blue) can be exhibited at a majority (e.g., about 50 to 90percent of the degrees (e.g., about 90 to 162 degrees when the degreeradius is 180) or about 50 to 80 percent or about 50 to 70 percent orabout 60 to 90 percent or about 70 to 90 percent of the degrees) ofangles of observation or illumination within a specific degree radius,while a second hue (e.g., blue-purple) or the second hue and/or a thirdhue (e.g., blue-green) can be exhibited at a minority (e.g., about 1 to49 percent of the degrees or about 10 to 35 percent or about 10 to 25percent of the degrees) of angles of observation or illumination withinthe specific degree radius.

When the multiple hues imparted by a multi-hued structural colors withlimited iridescence includes one or more hues which are not directlyadjacent to each other on the color wheel, the structural color canshift abruptly (e.g., changes quickly with a small (e.g., less than 15degrees, less than 10 degrees, less than 5 degrees) change in theobservation angle) from the first hue to the second hue as the angle ofobservation or illumination is varied, since the hues located on thecolor wheel between the imparted hues are omitted or “skipped over” andnot imparted. For example, for a multi-hued structural color withlimited iridescence which exhibits the hues of orange-red andyellow-green, when the angle of observation or illumination is variedwithin a 360 radius (or other specific radius, for example 180 degress),a plurality of intermediate hues between orange-red and yellow-green,such as orange, yellow-orange, and yellow, as well as hues on eitherside of orange-red and yellow-green, such as red, red-orange, etc. (huesrepresenting colors of light having shorter wavelengths than orange-red)and green, green-yellow, green, blue, etc. (hues representing colors oflight having longer wavelengths than yellow-green) are not imparted.

In an aspect, when the multiple hues imparted by a multi-hued structuralcolors with limited iridescence includes one or more hues which aredirectly adjacent to each other on the color wheel (e.g., hues which areanalogous) or which are not directly adjacent to each other (e.g.,complementary or split complementary hues, hues exhibiting a triadic ortetradic harmony, etc.) on the color wheel, the structural color canshift abruptly (e.g., changes quickly with a small (e.g., less than 15degrees, less than 10 degrees, less than 5 degrees) change in theobservation angle) from the first hue to the second hue as the angle ofobservation or illumination is varied. In another aspect, when themultiple hues imparted by a multi-hued structural colors with limitediridescence includes one or more hues which are directly adjacent toeach other on the color wheel or which are not directly adjacent to eachother on the color wheel, the structural color can shift gradually(e.g., changes over a long (e.g., great than 15 degrees, greater than 20degrees, greater than 30 degrees) change in the observation angle) fromthe first hue to the second hue as the angle of observation orillumination is varied.

Similarly, other properties of the structural color, such as thelightness of the color, the saturation of the color, and the purity ofthe color, among others, can be substantially the same regardless of theangle of observation or illumination, or can vary depending upon theangle of observation or illumination. The structural color can have amatte appearance, a glossy appearance, or a metallic appearance, or acombination thereof.

As discussed above, the color (including hue) of a structurally-coloredarticle (e.g., an article including an structural color) can varydepending upon the angle at which the structurally-colored article isobserved or illuminated. The hue or hues of an article can be determinedby observing the article, or illuminating the article, at a variety ofangles using constant lighting conditions. As used herein, the “angle”of illumination or viewing is the angle measured from an axis or planethat is orthogonal to the surface. The viewing or illuminating anglescan be set between about 0 and 180 degrees. The viewing or illuminatingangles can be set at 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60degrees, and −15 degrees and the color can be measured using acolorimeter or spectrophotometer (e.g., manufactured by Konica, Minolta,etc.), which focuses on a particular area of the article to measure thecolor. The viewing or illuminating angles can be set at 0 degrees, 15degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 90 degrees, 105degrees, 120 degrees, 135 degrees, 150 degrees, 165 degrees, 180degrees, 195 degrees, 210 degrees, 225 degrees, 240 degrees, 255degrees, 270 degrees, 285 degrees, 300 degrees, 315 degrees, 330degrees, and 345 degrees and the color can be measured using acolorimeter or spectrophotometer. In a particular example of amulti-hued article colored using only structural color can exhibitmulti-hued structural color with limited iridescence, when measured at 0degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, and −15degrees, the hues measured for the article consisted of “blue” at threeof the measurement angles, “blue-green” at 2 of the measurement anglesand “purple” at one of the measurement angles.

Various methodologies exist for defining color coordinate systems andfor assigning color space coordinates to a color. One example is L*a*b*color space, where, for a given illumination condition, L* is a valuefor lightness, and a* and b* are values for color-opponent dimensionsbased on the CIE coordinates (CIE 1976 color space or CIELAB). In anembodiment, a structurally-colored article having structural color canbe considered as having a “single” color when the change in colormeasured for the article is within about 10% or within about 5% of thetotal scale of the a* or b* coordinate of the L*a*b* scale (CIE 1976color space) at three or more measured observation or illuminationangles selected from measured at observation or illumination angles of 0degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, and −15degrees.

A difference between two color measurements can be describedmathematically in the CIELAB space based on the differences between thecolor coordinates of the two colors. For example, a first measurementhas coordinates L₁*, a₁* and b₁*, and a second measurement hascoordinates L₂*, a₂* and b₂*. The total difference between these twomeasurements on the CIELAB scale can be expressed as ΔE*_(ab), which iscalculated as follows:ΔE*_(ab)=[(L₁*−L₂*)²+(a₁*−a₂*)²+(b₁*−b₂*)²]^(1/2). Generally speaking,if two colors have a ΔE*_(ab) of less than or equal to 1, the differencein color is not perceptible to human eyes, and if two colors have aΔE*_(ab) of greater than 100 the colors are considered to be oppositecolors, while a ΔE*_(ab) of about 2-3, or of 3 or more, is consideredthe threshold for perceivable color difference by most humans.

In an aspect, a first structural color (e.g., imparted to a firstsection or article) and a second structural color (e.g., imparted to asecond section or article) can be considered different structural colorsif they have a ΔE*_(ab) of greater than 2.2, greater than 3, greaterthan 4, greater than 5, or greater than 10. In another aspect, a firststructural color (e.g., imparted to a first section) and a secondstructural color (e.g., imparted to a second section) can be consideredthe same structural color if they have a ΔE*_(ab) of less about 3 orless than 2.2.

In another aspect, a first section can be considered as having a“single” color when the ΔE*_(ab) is less than 3, or less than 2.2,between pairs of measurements across three or more measured observationor illumination angles selected from measured at observation orillumination angles of 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60degrees, and −15 degrees. In yet another aspect, a first section can becan be considered to be multi-hued when the ΔE*_(ab) between at leastone pair of measurements is greater than 2.2, greater than 3, greaterthan 4, greater than 5, or greater than 10, where the measurements aretaken at each of three or more observation or illumination angles chosenfrom 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, and −15degrees. In an aspect, the first section can be multi-hued by imparting2 different structural colors, multi-hued by imparting 3 differentstructural colors, or multi-hued by imparting 4 different structuralcolors, each at different angles of observation or illumination (e.g.,about 15 degrees or more apart).

In the CIELAB space, the threshold of perceptible color difference basedon the ΔE*_(ab) calculation is about 2-3 and the perception of color bya viewer is dependent upon the physiology of the viewer, the viewingconditions, and the like, an individual viewer observing the firststructural color and the second structural color may not be able todetect that the two structural colors are different, while the twostructural colors may be considered to be different based on theΔE*_(ab) calculation, or based on a difference between their a*coordinates, their b* coordinates, or their a* and b* coordinates.

Similarly, the structural color at two different angles can beconsidered as corresponding substantially to one another by measuringaccording to the CIE 1976 color space, under a given illuminationcondition. The illumination condition can be at a single observationangle of about −15 to 180 degrees or about −15 and 60 degreesperpendicular the horizontal plane of the optical element (e.g., theplane parallel the layers of the optical element). A first colormeasurement at a first angle of observation having coordinates L₁* anda₁* and b₁* over the wavelength range of 380 to 625 nanometers can beobtained. In addition, a second color measurement at the first angle ofobservation having coordinates L₂* and a₂* and b₂* over the firstwavelength value can be obtained. The structural color can be comparedin different ways. In one approach described above,ΔE*_(ab)=[(L₁*−L₂*)²+(a₁*−a₂*)² (b₁*−b₂*)²]^(1/2), can be used tocompare the first color measurement and the second color measurement.The first structural color and the second structural color can beconsidered the same or substantially indistinguishable when the ΔE*_(ab)between the first color measurement and the second color measurement canbe less than or equal to about 3, or optionally the ΔE*_(ab) can bebetween the first color measurement and the second color measurement isless than or equal to about 2.2. If ΔE*_(ab) is greater than 3, then thefirst structural color and the second structural color are different.

In another aspect, the minimum percent of reflectance of the wavelengthrange, the at least one peak, or set of peaks is independent of theangle of incident light upon the optical element. The structural coloris independent upon observation angle. Alternatively, the minimumpercent of reflectance of the wavelength range, the at least one peak,or set of peaks is dependent of the angle of incident light upon theoptical element. The structural color is dependent upon observationangle.

The observation angle independence or dependence of a structural colorcan be determined. At a first observation angle the structural color isa first structural color and at a second observation angle thestructural color is a second structural color. The first structuralcolor and the second structural color can be the same or different. Thesimilarity or difference in the first structural color and the secondstructural color at their respective angles of observation can bedetermined according to the CIE 1976 color space under a givenillumination condition at two observation angles of about −15 to 180degrees or about −15 degrees and +60 degrees and which are at least 15degrees apart from each other. A first color measurement at the firstobservation angle having coordinates L₁* and a₁* and b₁* can beobtained. A second color measurement at the second observation anglehaving coordinates L₂* and a₂* and b₂* can be obtained. ΔE*_(ab), asdescribed above and herein, ΔE*_(ab)=[(L₁*−L₂*)² (a₁*−a₂*)²(b₁*−b₂*)²]^(1/2), can be used to correlate the first structural colorand the second structural color at their angles of observation. When theΔE*_(ab) between the first color measurement and the second colormeasurement is less than or equal to about 2.2, or optionally theΔE*_(ab) between the first color measurement and the second colormeasurement is less than or equal to about 3, then the first structuralcolor and the second structural color are the same or indistinguishableto the average observer. The first structural color and the secondstructural color are considered distinguishable or different when theΔE*_(ab) between the first color measurement and the second colormeasurement is greater than 3, or optionally wherein the ΔE*_(ab)between the first color measurement and the second color measurement isgreater than or equal to about 4 or 5, or 10.

Another example of a color scale is the CIELCH color space, where, for agiven illumination condition, L* is a value for lightness, C* is a valuefor chroma, and h° denotes a hue as an angular measurement. In anaspect, a first structural color (e.g., imparted to a first section orarticle using an optical element) and a second structural color (e.g.,imparted to a second section or article using an optical element) can beconsidered to have the same color or hue when the hue measured for thefirst section is less than 10 degrees different or less than 5 degreesdifferent than the hue measured for the second section at the h° angularcoordinate of the CIELCH color space, at three or more measuredobservation or illumination angles selected from measured at observationor illumination angles of 0 degrees, 15 degrees, 30 degrees, 45 degrees,60 degrees, and −15 degrees. In a further aspect, a first structuralcolor (e.g., imparted to a first section or article) and a secondstructural color (e.g., imparted to a second section or article) can beconsidered to have different colors or hues when the hue measured forthe first section is at least 25 or is at least 45 degrees differentthan the hue measured for the second section at the h° angularcoordinate of the CIELCH color space, at three or more measuredobservation or illumination angles selected from measured at observationor illumination angles of 0 degrees, 15 degrees, 30 degrees, 45 degrees,60 degrees, and −15 degrees. In another aspect, an optical element canbe said to be single-hued when all areas of the optical element have thesame color in the CIELCH color space as defined herein, or can bemulti-hued or multi-colored when at least two areas of the opticalelement have different colors in the CIELCH color space.

Another system for characterizing color includes the “PANTONE” MatchingSystem (Pantone LLC, Carlstadt, N.J., USA), which provides a visualcolor standard system to provide an accurate method for selecting,specifying, broadcasting, and matching colors through any medium. In anexample, a first optical element and a second optical element can besaid to have the same color when the color measured for each opticalelement is within a certain number of adjacent standards, e.g., within20 adjacent PANTONE standards, at three or more measured observation orillumination angles selected from 0 degrees, 15 degrees, 30 degrees, 45degrees, 60 degrees, and 75 degrees. In an alternative aspect, the firstoptical element and the second optical element can be said to havedifferent colors when the color measured for each optical element isoutside a certain number of adjacent standards, e.g., at least 20adjacent PANTONE standards or farther apart, at three or more measuredobservation or illumination angles selected from 0 degrees, 15 degrees,30 degrees, 45 degrees, 60 degrees, and 75 degrees. In another aspect,an optical element can be said to be single-hued when all areas of theoptical element have the same PANTONE color as defined herein, or can bemulti-hued or multi-colored when at least two areas of the opticalelement have different PANTONE colors.

Another example of a color scale is the Natural Color System® or NCS,which is built on principles of human physiological vision and describescolor by using color similarity relationships. The NCS is based on thepremise that the human visual system consists of six elementary colorprecepts, or colors that can be challenging to define perceptually interms of other colors. These colors consist of three pairs: (i) theachromatic colors of black (S) and white (W), (ii) the opposing primarycolor pair of red (R) and green (G), and (iii) the opposing primarycolor pair of yellow (Y) and blue (B). In the NCS, any color that can beperceived by the human eye can be similar to the two achromatic colorsand a maximum of two non-opposing primary colors. Thus, for example, aperceived color can have similarities to red and blue but not to red andgreen. NCS descriptions of colors are useful for colors that belong tothe surfaces of materials, so long as the surfaces are not fluorescent,translucent, luminescent, or the like; the NCS does not encompass othervisual properties of the surface such as, for example, gloss andtexture.

The NCS color space is a three dimensional model consisting of a flatcircle at which the four primary colors are positioned in order at 0degrees, 90 degrees, 180 degrees, and 270 degrees. For example, ifyellow is at 0 degrees, red is at 90 degrees, blue is at 180 degrees,and green is at 270 degrees. White is represented above the circle andblack below such that a hue triangle forms between the black/white(grayscale) axis and any point on the circle.

Percentage “blackness” (s) is defined in the NCS as a color's similarityto the elementary color black. Percentage “chromaticness” (c) representssimilarity to the most saturated color in a hue triangle. “Hue” (ϕ) inthe NCS, meanwhile, represents similarity of a color to one or at mosttwo non-opposing primary colors. Blackness and chromaticness add up to avalue less than or equal to 100 percent; any remaining value is referredto as “whiteness” (w) of a color. In some cases, the NCS can be used tofurther describe “saturation” (m), a value from 0 to 1 determined interms of chromaticness and whiteness (e.g., m=c/(w+c)). NCS can furtherbe used to describe “lightness” (v), a description of whether the colorcontains more of the achromatic elementary colors black or white. A pureblack article would have a lightness of 0 and a pure white article wouldhave a lightness of 1. Purely neutral grays (c=0) have lightness definedby v=(100−s)/100, while chromatic colors are first compared to areference scale of grays and lightness is then calculated as for grays.

NCS notation takes the generic form sc-AϕB, where sc defines “nuance,”ss is the percent blackness and cc refers to the chromaticity; A and Bare the two primary colors to which the color relates; and ϕ is ameasure of where a color falls between A and B. Thus, a color (e.g.,orange) that has equal amounts of yellow and red could be representedsuch that AϕB=Y50R (e.g., yellow with 50 percent red), whereas a colorhaving relatively more red than yellow is represented such thatAϕB=Y60R, Y70R, Y80R, Y90R, or the like. The color having equal amountsof yellow and red with a relatively low (10 percent) amount of darknessand a medium (50 percent) level of chromaticity would thus berepresented as 1050-Y50R. In this system, neutral colors having noprimary color components are represented by sc-N, where sc is defined inthe same manner as with a non-neutral color and N indicates neutrality,while a pure color would have a notation such as, for example, 3050-B(for a blue with 30 percent darkness and 50 percent chromaticity). Acapital “S” in front of the notation indicates that a value was presentin the NCS 1950 Standard, a reduced set of samples. As of 2004, the NCSsystem contains 1950 standard colors.

The NCS is more fully described in ASTM E2970-15, “Standard Practice forSpecifying Color by the Natural Colour System (NCS).” Although the NCSis based on human perception and other color scales such as the CIELABor CIELCH spaces may be based on physical properties of objects, NCS andCIE tristimulus values are interconvertible.

The method of making the structurally colored article can includedisposing (e.g., affixing, attaching, bonding, fastening, joining,appending, connecting, binding) the optical element onto an article(e.g., an article of footwear, an article of apparel, an article ofsporting equipment, etc.) in an “in-line” or “on its side”configuration. The article includes a component, and the component has asurface upon which the optical element can be disposed. The surface ofthe article can be made of a material such as a thermoplastic materialor thermoset material, as described herein. For example, the article hasa surface including a thermoplastic material (i.e., a firstthermoplastic material), for example an externally-facing surface of thecomponent or an internally-facing surface of the component (e.g., anexternally-facing surface or an internally-facing surface a bladder).The optical element can be disposed onto the thermoplastic material, forexample. The surface upon which the optical element is disposed is notopaque and is semi-transparent or transparent to light in from 380 to740 nanometers, for example, the surface can have a minimum percenttransmittance of about 30 percent or more, about 40 percent or more, orabout 50 percent or more, for light in the visible spectrum.

In an aspect, the temperature of at least a portion of the first surfaceof the article including the thermoplastic material is increased to atemperature at or above creep relaxation temperature (Tcr), Vicatsoftening temperature (Tvs), heat deflection temperature (Thd), and/ormelting temperature (Tm) of the thermoplastic material, for example tosoften or melt the thermoplastic material. The temperature can beincreased to a temperature at or above the creep relaxation temperature.The temperature can be increased to a temperature at or above the Vicatsoftening temperature. The temperature can be increased to a temperatureat or above the heat deflection temperature. The temperature can beincreased to a temperature at or above the melting temperature. Whilethe temperature of the at least a portion of the first side of thearticle is at or above the increased temperature (e.g., at or above thecreep relaxation temperature, the heat deflection temperature, the Vicatsoftening temperature, or the melting temperature of the thermoplasticmaterial), the optical element is affixed to the thermoplastic materialwithin the at least a portion of the first side of the article.Following the affixing, the temperature of the thermoplastic material isdecreased to a temperature below its creep relaxation temperature to atleast partially re-solidify the thermoplastic material. Thethermoplastic material can be actively cooled (e.g., removing the sourcethat increases the temperature and actively (e.g., flowing cooler gasadjacent the article reducing the temperature of the thermoplasticmaterial) or passively cooled (e.g., removing the source that increasesthe temperature and allowing the thermoplastic layer to cool on itsown).

Now having described color and other aspects generally, additionaldetails regarding the optical element are provided. As described herein,the article includes the optical element. FIG. 3 illustrates across-sectional view (upper) and top view (lower) of an article 400. Thetop view (lower illustration) shows areas of different structural colors(e.g., first structural color 426, second structural color 446) asdenoted by “R” and “Y” for the article 400. These correspond to thesections of the optical element 410 shown in the cross-sectional view(upper illustration, first section 422, second section 442,respectively), where the top view of the structural colors line-up withthe different areas (e.g., first area 420 and second area 440) of thearticle 400 in the cross-sectional view directly above. The opticalelement 410 includes a first section 422 and a second section 442. Eachsection includes a different number of layers, and as shown in FIG. 3,six and four layers, respectively. The first section 422 has a firstsection average thickness 424 and the second section 442 has a secondsection average thickness 444, where the first section average thickness424 and the second section average thickness 444 are different.

An adjacent section can have a section average thickness (e.g., thefirst section average thickness 424 and the second section averagethickness 444) of about 5 to 90 percent, about 5 to 80 percent, about 10to 70, about 10 to 60 percent, about 20 to 50 percent of the thicknessof the first section average thickness. Similarly, an adjacent sectioncan have a section average thickness of about 105 to 500 percent, about105 to 400 percent, about 110 to 300, about 110 to 200 percent, about120 to 150 percent of the thickness of the first section averagethickness. For example in FIG. 3, the second section average thickness444 can be about 5 to 90 percent, about 5 to 80 percent, about 10 to 70,about 10 to 60 percent, about 20 to 50 percent of the thickness of thefirst section average thickness 424.

The corresponding layers of the first section 422 and the second section442 have the same average thicknesses. Each layer of the first section422 corresponds to a layer in the second section 442 (e.g., first layer432A in the first section 422 corresponds to the first layer 432A of thesecond section 442), while the second section 442 does not include twolayers in the first section 422. Each layer in each section has anaverage thickness (e.g., a first layer 432A in the first section 422 hasa first section first layer average thickness 424, a second layer 432Bin the second section 442 has a second section second layer averagethickness 444), where vertically adjacent layers can have the same ordifferent thicknesses.

In addition, at least one layer (e.g., 432A-432D) extends across each ofthe sections, where the average thickness is the same among thesections. For example, FIG. 3 illustrates that multiple layers 432A-432Dextend over each of the two sections and the average thickness for eachcorresponding layer in each section is the same.

The first section 422 of the optical element 410 imparts a firststructural color 426 to the first area 420 of the article 400 and thesecond section 442 of the optical element 410 imparts a secondstructural color 446 to the second area 440 of the article 400, each arerepresented in the top view (lower view). The first structural color 426and the second structural color 446 each differ from one other whenviewed from the same angle of observation. The difference can at leastin part be attributed to the different average thicknesses of thedifferent sections. It should be stated that while a clear demarcationis represented, there may be an area of transition between the firststructural color 426 and the second structural color 446. For clarityand illustration, a set demarcation line is shown. In an aspect, thetransition my be abrupt (e.g., transitions directly from one structuralcolor to another structural color).

The material of each of the corresponding layers of the first section422 and the second section 442 consist essentially of the same material(e.g., they are the same material, less contaminants which are less thatabout 1 percent, less that about 2 percent, less that about 3 percent orless that about 5 percent) or are the same material (e.g., about 98percent or more or about 99 percent or more). Vertically adjacent layersare made of different materials.

The refractive index of adjacent layers of each section are different.The difference in the index of refraction of adjacent layers can beabout 0.0001 to 50 percent, about 0.1 to 40 percent, about 0.1 to 30percent, about 0.1 to 20 percent, about 0.1 to 10 percent (and otherranges there between (e.g., the ranges can be in increments of 0.0001 to5 percent)). The index of refraction depends at least in part upon thematerial of the layer and can range from 1.3 to 2.6.

While not illustrated in FIG. 3, the optical element can include a thirdsection disposed on a third area of the article. The third section ofthe optical element imparts a third structural color to the third areaof the article. A color parameter such as a hue, a value, a chroma orany combination thereof of the first structural color, the secondstructural color, and the third structural color are different. Thethird section has a third number of layers, where the first number oflayers, the second number of layers, and the third number of layers aredifferent. At least the first layer for each of the first section, thesecond section, and the third section are made of the same material.Each of the layers of the third section have the same thickness of thecorresponding layers in the first section.

The structural color imparted by a first section and a second sectioncan be compared. A color measurement can be performed for each of thefirst section and second section at the same relative angle. Forexample, at a first observation angle the structural color is a firststructural color for the first section and at first observation anglethe structural color is a second section for the second optical element.The first color measurement can be obtained and has coordinates L₁* anda₁* and b₁*, while a second color measurement can be obtained and hascoordinates L₂* and a₂* and b₂* can be obtained, according to the CIE1976 color space under a given illumination condition.

When ΔE*_(ab) between the first color measurement and the second colormeasurement is less than or equal to about 2.2 or is less than or equalto about 3, the first structural color associated with the first colormeasurement and the second structural color associated with the secondcolor measurement are the same or not perceptibly different to anaverage observer. When ΔE*_(ab) between the first color measurement andthe second color measurement is greater than 3 or optionally greaterthan about 4 or 5, the first structural color associated with the firstcolor measurement and the second structural color associated with thesecond color measurement are different or perceptibly different to anaverage observer.

In another approach, when the percent difference between one or more ofvalues L₁* and L₂* a₁* and a₂*, and b₁* and b₂* is less than 20 percent,the first structural color associated with the first color measurementand the second structural color associated with the second colormeasurement are the same or not perceptibly different to an averageobserver. When the percent difference between one or more of values L₁*and L₂* a₁* and a₂*, and b₁* and b₂* is greater than 20 percent, thefirst structural color associated with the first color measurement andthe second structural color associated with the second color measurementare different or perceptibly different to an average observer.

The optical element can be an inorganic optical element, an organicoptical element, or a mixed inorganic/organic optical element. Theorganic optical element has at least one layer and that layer is made ofan organic material. The organic material can include a polymer, such asthose described herein. The organic material is made of a non-metal ornon-metal oxide material. The organic material that does not include ametal or metal oxide. The organic material is made of a polymericmaterial that does not include a metal or metal oxide.

The inorganic optical element has at least one layer and that layer ismade of a non-organic material. As described in detail herein, thenon-organic material can be a metal or metal oxide. The non-organicmaterial does not include any organic material.

The optical element can be a mixed inorganic/organic optical element,meaning that one or more of the layers can be made of an inorganicmaterial, one or more layers can be made of an organic material, and/orone or more layers can be made of a layer of a mixture of inorganic andorganic materials (e.g., a polymer include metal or metal oxideparticles (e.g., micro- or nano-particles).

The optical element includes at least one layer, which can be at leastone constituent layer and/or at least one reflective layer (e.g.,intermediate and/or non-intermediate reflective layers). The opticalelement that can be or include a single layer reflector, a single layerfilter, or multilayer reflector or a multilayer filter. The opticalelement can function to modify the light that impinges thereupon so thatstructural color is imparted to the article. The optical element canalso optionally include one or more additional layers (e.g., aprotective layer, the textured layer, a polymeric layer, and the like).The optical element can have a thickness of about 100 to 1,500nanometers, about 100 to 1,200 nanometers, about 100 to about 700nanometers, or of about 200 to about 500 nanometers.

The optical element or layers or portions thereof (e.g., reflectivelayer, constituent layer) can be formed using known techniques such asphysical vapor deposition, electron beam deposition, atomic layerdeposition, molecular beam epitaxy, cathodic arc deposition, pulsedlaser deposition, sputtering deposition (e.g., radio frequency, directcurrent, reactive, non-reactive), chemical vapor deposition,plasma-enhanced chemical vapor deposition, low pressure chemical vapordeposition and wet chemistry techniques such as layer-by-layerdeposition, sol-gel deposition, Langmuir blodgett, and the like, whichcan optionally use techniques (e.g., masks) to control the thickness ofa layer in one or more areas of the surface of the article. Thetemperature of the first side can be adjusted using the technique toform the optical element and/or a separate system to adjust thetemperature.

As stated herein, the optical element can comprise a single layer ormultilayer reflector (e.g., reflective layer(s) and/or constituentlayer(s)). The multilayer reflector can be configured to have a certainreflectivity at a given wavelength of light (or range of wavelengths)depending, at least in part, on the material selection, thickness andnumber of the layers of the multilayer reflector. In other words, onecan judiciously select the materials, thicknesses, and numbers of thelayers of a multilayer reflector and optionally its interaction with oneor more other layers, so that it can reflect a certain wavelength oflight (or range of wavelengths), to produce a desired structural color.

The optical element can include 2 to 20 layers, 2 to 15, 2 to 10 layer,2 to 6 layers, or 2 to 4 layers, where at least two sections have adifferent number of layers. The number of layers the at least twosection can differ by at least 1, at least 2, at least 3, at least 4, atleast 5, at least 10, at least 15, at least 20, and so on. Each layercan have a thickness that is about one-fourth of the wavelength of lightto be reflected to produce the desired structural color. Each layer canhave a thickness of at least 10 nanometers, optionally at least 30nanometers, at least 40 nanometers, at least 50 nanometers, at least 60nanometers, at least 100 nanometers, at least 150 nanometers, optionallya thickness of from about 10 nanometers to about 500 nanometers, about10 nanometers to about 250 nanometers, about 10 nanometers to about 200nanometers, about 10 nanometers to about 150 nanometers, about 10nanometers to about 100 nanometers, or of from about 30 nanometers toabout 80 nanometers, or from about 40 nanometers to about 60 nanometers.For example, the layer can be about 30 to 200 nanometers or about 30 to150 nanometers thick.

The optical element can comprise a single layer or multilayer filter.The single layer or multilayer filter destructively interferes withlight that impinges upon the article, where the destructive interferenceof the light and optionally interaction with one or more other layers orstructures of the optical element (e.g., a multilayer reflector, atextured structure) impart the structural color. In this regard, thelayer of the single layer filter or the layers of the multilayer filtercan be designed (e.g., material selection, thickness, number of layer,and the like) so that a single wavelength of light, or a particularrange of wavelengths of light, make up the structural color. Forexample, the range of wavelengths of light can be limited to a rangewithin plus or minus 30 percent or a single wavelength, or within plusor minus 20 percent of a single wavelength, or within plus or minus 10percent of a single wavelength, or within plus or minus 5 percent or asingle wavelength. The range of wavelengths can be broader to produce amore iridescent structural color.

Each layer can independently include a metal layer or an oxide layer.The oxide layer can be a metal oxide, a doped metal oxide, or acombination thereof. The metal layer, the metal oxide or the doped metaloxide can include the following: the transition metals, the metalloids,the lanthanides, and the actinides, as well as nitrides, oxynitrides,sulfides, sulfates, selenides, tellurides and a combination of these.The metal layer can be titanium, aluminum, silver, zirconium, chromium,magnesium, silicon, gold, platinum, and a combination thereof. The metaloxide can include titanium oxide, silver oxide, aluminum oxide, silicondioxide, tin dioxide, chromia, iron oxide, nickel oxide, silver oxide,cobalt oxide, zinc oxide, platinum oxide, palladium oxide, vanadiumoxide, molybdenum oxide, lead oxide, and combinations thereof as well asdoped versions of each. In some aspects, the layer can consistessentially of a metal oxide. In some aspects, the layer can consistessentially of titanium dioxide. The metal oxide can be doped withwater, inert gasses (e.g., argon), reactive gasses (e.g., oxygen ornitrogen), metals, and a combination thereof. In some aspects, thereflective layer can consist essentially of a doped metal oxide or adoped metal oxynitride or both. In an aspect, the reflective layer canbe made of Ti or TiTiO_(x) (x=1-2). The density of the Ti layer orTiO_(x) layer can be about 3 to 6 grams per centimeter cubed, about 3 to5 grams per centimeter cubed, about 4 to 5 grams per centimeter cubed,or 4.5 grams per centimeter cubed.

In addition, each layer can be made of liquid crystals. Each layer canbe made of a material such as: silicon dioxide, titanium dioxide, zincsulfide, magnesium fluoride, tantalum pentoxide, aluminum oxide, or acombination thereof. To improve adhesion between layers, a metal layeris adjacent a metal oxide layer formed of the same metal. For example,Ti and TiO_(x) can be positioned adjacent one another to improveadhesion.

The material of the layer can be selected based on the desiredstructural color to be produced. Select materials reflect somewavelengths more than other wavelengths. In this way, the material ofthe layer can be selected based on the desired structural color. Theoptical element can be made with a combination of constituent layersand/or reflective layers so that the desired structural color isimparted. The optical element including a reflective layer can have aminimum percent reflectance for one or more of the following wavelengthranges: violet 380 to 450 nanometer, blue 450 to 485 nanometer, cyan 485to 500 nanometer, green 500 to 565 nanometer, yellow 564 to 590nanometer, orange 590 to 625 nanometer, or red 625 to 740 nanometer. Thereflective layer can have a minimum percent reflectance for one or morewavelength widths (e.g., about 10 nanometers, about 20 nanometers, about30 nanometers, about 40 nanometers, about 50 nanometers, about 60nanometers, about 75 nanometers, or about 100 nanometers) in the rangefrom 380 to 740 nanometers. For the ranges not selected in a particularconfiguration, the minimum reflectivity is lower than that for theselected range, for example, the minimum reflectivity is lower than thatfor the selected range by about 10 percent or more, about 20 percent ormore, about 30 percent or more, about 40 percent or more, or about 50percent or more. In an aspect, the reflective layer can be Al orAlO_(x), where the structural color is iridescent. In another example,the reflective layer can Ti or TiO_(x), where the structural color canbe one or more hues of blue or one or more hues of green, or acombination thereof.

The optical element can be a coating on the surface of the article. Thecoating can be chemically bonded (e.g., covalently bonded, ionicallybonded, hydrogen bonded, and the like) to the surface of the article.The coating has been found to bond well to a surface made of a polymericmaterial. In an example, the surface of the article can be made of apolymeric material such as a polyurethane, including a thermoplasticpolyurethane (TPU), as those described herein.

The optical element can be uncolored (e.g., no pigments or dyes added tothe structure or its layers), colored (e.g., pigments and/or dyes areadded to the structure or its layers (e.g., dark or black color)). Thesurface of the component upon which the optical element is disposed canbe uncolored (e.g., no pigments or dyes added to the material), colored(e.g., pigments and/or dyes are added to the material (e.g., dark orblack color)), reflective, and/or transparent (e.g., percenttransmittance of 75 percent or more).

The layers can be formed in a layer-by-layer manner, where each layerhas a different index of refraction. Each of layers can be formed usingknown techniques such as those described above and herein.

As mentioned above, the optical element can include one or more layersin addition to the reflective layer(s) and/or the constituent layer(s).The optical element has a first side and a second side, where the firstside or the second side is adjacent the surface of the component. Theone or more other layers of the optical element can be on the first sideand/or the second side of the optical element. For example, the opticalelement can include a protective layer and/or a polymeric layer such asa thermoplastic polymeric layer, where the protective layer and/or thepolymeric layer can be on one or both of the first side and the secondside of the optical element. One or more of the optional other layerscan include a textured surface. Alternatively or in addition, one ormore of the reflective layer(s) and/or one or more constituent layer(s)of the optical element can include a textured surface.

A protective layer can be disposed on the first and/or second side ofthe optical element, on the outside most layer to protect the opticalelement. The protective layer is more durable or more abrasion resistantthan the other layers. The protective layer is optically transparent tovisible light. The protective layer can be on the first side and/or thesecond side of the optical element to protect the other layers on therespective side. All or a portion of the protective layer can include adye or pigment in order to alter an appearance of the structural color.The protective layer can include silicon dioxide, glass, combinations ofmetal oxides, or mixtures of polymers. The protective layer can have athickness of about 3 nanometers to 1 millimeter.

The protective layer can be formed using physical vapor deposition,chemical vapor deposition, pulsed laser deposition, evaporativedeposition, sputtering deposition (e.g., radio frequency, directcurrent, reactive, non-reactive), plasma enhanced chemical vapordeposition, electron beam deposition, cathodic arc deposition, lowpressure chemical vapor deposition and wet chemistry techniques such aslayer by layer deposition, sol-gel deposition, Langmuir blodgett, andthe like. Alternatively or in addition, the protective layer can beapplied by spray coating, dip coating, brushing, spin coating, doctorblade coating, and the like.

A polymeric layer can be disposed on the first and/or the second side ofthe optical element. The polymeric layer can be used to dispose theoptical element onto an article, such as, for example, when the articledoes not include a thermoplastic material to adhere the optical element.The polymeric layer can comprise a polymeric adhesive material, such asa hot melt adhesive. The polymeric layer can be a thermoplastic materialand can include one or more layers. The thermoplastic material can beany one of the thermoplastic material described herein. The polymericlayer can be applied using various methodologies, such as spin coating,dip coating, doctor blade coating, and so on. The polymeric layer canhave a thickness of about 3 nanometer to 1 millimeter.

As described above, one or more embodiments of the present disclosureprovide articles that incorporate the optical element (e.g., single ormultilayer structures) on a side of a component of the article to impartstructural color. The optical element can be disposed onto thethermoplastic material of the side of the article, and the side of thearticle can include a textile, including a textile comprising thethermoplastic material.

Having described aspects, additional details will now be described forthe optional textured surface. As described herein, the article includesthe optical element and the optical element optionally include atextured surface. The textured surface can be a surface of a texturedstructure or a textured layer. The textured surface may be provided aspart of the optical element. For example, the optical element maycomprise a textured layer or a textured structure that comprises thetextured surface. The textured surface may be provided as part of thearticle to which the optical element is disposed. For example, theoptical element may be disposed onto the surface of the article wherethe surface of the article is a textured surface, or the surface of thearticle includes a textured structure or a textured layer affixed to it.

The textured surface (or a textured structure or textured layerincluding the textured surface) may be provided as a feature on or partof another medium, such as a transfer medium, and imparted to a side orlayer of the optical element or to the surface of the component. Forexample, a mirror image or relief form of the textured surface may beprovided on the side of a transfer medium, and the transfer mediumcontacts a side of the optical element or the surface of the componentin a way that imparts the textured surface to the optical element orarticle. While the various embodiments herein may be described withrespect to a textured surface of the optical element, it will beunderstood that the features of the textured surface, or a texturedstructure or textured layer, may be imparted in any of these ways.

The textured surface can contribute to the structural color resultingfrom the optical element. As described herein, structural coloration isimparted, at least in part, due to optical effects caused by physicalphenomena such as scattering, diffraction, reflection, interference orunequal refraction of light rays from an optical element. The texturedsurface (or its mirror image or relief) can include a plurality ofprofile features and flat or planar areas. The plurality of profilefeatures included in the textured surface, including their size, shape,orientation, spatial arrangement, etc., can affect the light scattering,diffraction, reflection, interference and/or refraction resulting fromthe optical element. The flat or planar areas included in the texturedsurface, including their size, shape, orientation, spatial arrangement,etc., can affect the light scattering, diffraction, reflection,interference and/or refraction resulting from the optical element. Thedesired structural color can be designed, at least in part, by adjustingone or more of properties of the profile features and/or flat or planarareas of the textured surface.

The profile features can extend from a side of the flat areas, so as toprovide the appearance of projections and/or depressions therein. A flatarea can be a flat planar area. A profile feature may include variouscombinations of projections and depressions. For example, a profilefeature may include a projection with one or more depressions therein, adepression with one or more projections therein, a projection with oneor more further projections thereon, a depression with one or morefurther depressions therein, and the like. The flat areas do not have tobe completely flat and can include texture, roughness, and the like. Thetexture of the flat areas may not contribute much, if any, to theimparted structural color. The texture of the flat areas typicallycontributes to the imparted structural color. For clarity, the profilefeatures and flat areas are described in reference to the profilefeatures extending above the flat areas, but the inverse (e.g.,dimensions, shapes, and the like) can apply when the profile featuresare depressions in the textured surface.

The textured surface can comprise a thermoplastic material. The profilefeatures and the flat areas can be formed using a thermoplasticmaterial. For example, when the thermoplastic material is heated aboveits softening temperature a textured surface can be formed in thethermoplastic material such as by molding, stamping, printing,compressing, cutting, etching, vacuum forming, etc., the thermoplasticmaterial to form profile features and flat areas therein. The texturedsurface can be imparted on a side of a thermoplastic material. Thetextured surface can be formed in a layer of thermoplastic material. Theprofile features and the flat areas can be made of the samethermoplastic material or a different thermoplastic material.

The textured surface generally has a length dimension extending along anx-axis, and a width dimension extending along a z-axis, and a thicknessdimension extending along a y-axis. The textured surface has a generallyplanar portion extending in a first plane that extends along the x-axisand the z-axis. A profile feature can extend outward from the firstplane, so as to extend above or below the plane x. A profile feature mayextend generally orthogonal to the first plane, or at an angle greaterto or less than 90 degrees to the first plane.

The dimensional measurements in reference to the profile features (e.g.,length, width, height, diameter, and the like) described herein refer toan average dimensional measurement of profile features in 1 squarecentimeter in the optical element.

The dimension (e.g., length, width, height, diameter, depending upon theshape of the profile feature) of each profile feature can be within thenanometer to micrometer range. A textured surface can have a profilefeature and/or flat area with a dimension of about 10 nanometers toabout 500 micrometers. The profile feature can have dimensions in thenanometer range, e.g., from about 10 nanometers to about 1000nanometers. All of the dimensions of the profile feature (e.g., length,width, height, diameter, depending on the geometry) can be in thenanometer range, e.g., from about 10 nanometers to about 1000nanometers. The textured surface can have a plurality of profilefeatures having dimensions that are 1 micrometer or less. In thiscontext, the phrase “plurality of the profile features” is meant to meanthat about 50 percent or more, about 60 percent or more, about 70percent or more, about 80 percent or more, about 90 percent or more, orabout 99 percent or more of the profile features have a dimension inthis range. The profile features can have a ratio of width:height and/orlength:height dimensions of about 1:2 and 1:100, or 1:5 and 1:50, or 1:5and 1:10.

The textured surface can have a profile feature and/or flat area with adimension within the micrometer range of dimensions. A textured surfacecan have a profile feature and/or flat area with a dimension of about 1micrometer to about 500 micrometers. All of the dimensions of theprofile feature (e.g., length, width, height, diameter, depending on thegeometry) can be in the micrometer range, e.g., from about 1 micrometerto about 500 micrometers. The textured surface can have a plurality ofprofile features having dimensions that are from about 1 micrometer toabout 500 micrometer. In this context, the phrase “plurality of theprofile features” is meant to mean that about 50 percent or more, about60 percent or more, about 70 percent or more, about 80 percent or more,about 90 percent or more, or about 99 percent or more of the profilefeatures have a dimension in this range. The height of the profilefeatures (or depth if depressions) can be about 0.1 and 50 micrometers,about 1 to 5 micrometers, or 2 to 3 micrometers. The profile featurescan have a ratio of width:height and/or length:height dimensions ofabout 1:2 and 1:100, or 1:5 and 1:50, or 1:5 and 1:10.

A textured surface can have a plurality of profile features having amixture of size dimensions within the nanometer to micrometer range(e.g., a portion of the profile features are on the nanometer scale anda portion of the profile features are on the micrometer scale). Atextured surface can have a plurality of profile features having amixture of dimensional ratios. The textured surface can have a profilefeature having one or more nanometer-scale projections or depressions ona micrometer-scale projection or depression.

The profile feature can have height and width dimensions that are withina factor of three of each other (0.33w≤h≤3w where w is the width and his the height of the profile feature) and/or height and lengthdimensions that are within a factor of three of each other (0.331≤h≤3lwhere l is the length and h is the height of the profile feature). Theprofile feature can have a ratio of length:width that is from about 1:3to about 3:1, or about 1:2 to about 2:1, or about 1:1.5 to about 1.5:1,or about 1:1.2 to about 1.2:1, or about 1:1. The width and length of theprofile features can be substantially the same or different.

In another aspect, the textured surface can have a profile featureand/or flat area with at least one dimension in the mid-micrometer rangeand higher (e.g., greater than 500 micrometers). The profile feature canhave at least one dimension (e.g., the largest dimension such as length,width, height, diameter, and the like depending upon the geometry orshape of the profile feature) of greater than 500 micrometers, greaterthan 600 micrometers, greater than 700 micrometers, greater than 800micrometers, greater than 900 micrometers, greater than 1000micrometers, greater than 2 millimeters, greater than 10 millimeters, ormore. For example, the largest dimension of the profile feature canrange from about 600 micrometers to about 2000 micrometers, or about 650micrometers to about 1500 micrometers, or about 700 micrometers to about1000 micrometers. At least one or more of the dimensions of the profilefeature (e.g., length, width, height, diameter, depending on thegeometry) can be in the micrometer range, while one or more of the otherdimensions can be in the nanometer to micrometer range (e.g., less than500 micrometers, less than 100 micrometers, less than 10 micrometers, orless than 1 micrometer). The textured surface can have a plurality ofprofile features having at least one dimension that is in themid-micrometer or more range (e.g., 500 micrometers or more). In thiscontext, the phrase “plurality of the profile features” is meant to meanthat about 50 percent or more, about 60 percent or more, about 70percent or more, about 80 percent or more, about 90 percent or more, orabout 99 percent or more of the profile features have at least onedimension that is greater than 500 micrometers. In particular, at leastone of the length and width of the profile feature is greater than 500micrometers or both the length and the width of the profile feature isgreater than 500 micrometers. In another example, the diameter of theprofile feature is greater than 500 micrometers. In another example,when the profile feature is an irregular shape, the longest dimension isgreater than 500 micrometers.

In aspects, the height of the profile features can be greater than 50micrometers. In this context, the phrase “plurality of the profilefeatures” is meant to mean that about 50 percent or more, about 60percent or more, about 70 percent or more, about 80 percent or more,about 90 percent or more, or about 99 percent or more of the profilefeatures have at height that is greater than 50 micrometers. The heightof the profile feature can be 50 micrometers, about 60 micrometers,about 70 micrometers, about 80 micrometers, about 90 micrometers, orabout 100 micrometers to about 60 micrometers, about 70 micrometers,about 80 micrometers, about 90 micrometers, about 100 micrometers, about150 micrometers, about 250 micrometers, about 500 micrometers or more.For example, the ranges can include 50 micrometers to 500 micrometers,about 60 micrometers to 250 micrometers, about 60 micrometers to about150 micrometers, and the like. One or more of the other dimensions(e.g., length, width, diameter, or the like) can be in the nanometer tomicrometer range (e.g., less than 500 micrometers, less than 100micrometers, less than 10 micrometers, or less than 1 micrometer). Inparticular, at least one of the length and width of the profile featureis less than 500 micrometers or both the length and the width of theprofile feature is less than 500 micrometers, while the height isgreater than 50 micrometers. One or more of the other dimensions (e.g.,length, width, diameter, or the like) can be in the micrometer tomillimeter range (e.g., greater than 500 micrometers to 10 millimeters).

The dimension (e.g., length, width, height, diameter, depending upon theshape of the profile feature) of each profile feature can be within thenanometer to micrometer range. The textured surface can have a profilefeature and/or flat area with a dimension of about 10 nanometers toabout 500 micrometers or higher (e.g., about 1 millimeter, about 2millimeters, about 5 millimeters, or about 10 millimeters). At least oneof the dimensions of the profile feature (e.g., length, width, height,diameter, depending on the geometry) can be in the nanometer range(e.g., from about 10 nanometers to about 1000 nanometers), while atleast one other dimension (e.g., length, width, height, diameter,depending on the geometry) can be in the micrometer range (e.g., 5micrometers to 500 micrometers or more (e.g., about 1 to 10millimeters)). The textured surface can have a plurality of profilefeatures having at least one dimension in the nanometer range (e.g.,about 10 to 1000 nanometers) and the other in the micrometer range(e.g., 5 micrometers to 500 micrometers or more). In this context, thephrase “plurality of the profile features” is meant to mean that about50 percent or more, about 60 percent or more, about 70 percent or more,about 80 percent or more, about 90 percent or more, or about 99 percentor more of the profile features have at least one dimension in thenanometer range and at least one dimension in the micrometer range. Inparticular, at least one of the length and width of the profile featureis in the nanometer range, while the other of the length and the widthof the profile feature is in the micrometer range.

In aspects, the height of the profile features can be greater than 250nanometers. In this context, the phrase “plurality of the profilefeatures” is meant to mean that about 50 percent or more, about 60percent or more, about 70 percent or more, about 80 percent or more,about 90 percent or more, or about 99 percent or more of the profilefeatures have at height that is greater than 250 nanometers. The heightof the profile feature can be 250 nanometers, about 300 nanometers,about 400 nanometers, or about 500 nanometers, to about 300 nanometers,about 400 nanometers, about 500 nanometers, or about 1000 nanometers ormore. For example, the range can be 250 nanometers to about 1000nanometers, about 300 nanometers to 500 nanometers, about 400 nanometersto about 1000 nanometers, and the like. One or more of the otherdimensions (e.g., length, width, diameter, or the like) can be in themicrometer to millimeter range (e.g., greater than 500 micrometers to 10millimeters). In particular, at least one of the length and width of theprofile feature is in the nanometer range (e.g., about 10 to 1000nanometers) and the other in the micrometer range (e.g., 5 micrometersto 500 micrometers or more), while the height is greater than 250nanometers.

The profile features can have a certain spatial arrangement. The spatialarrangement of the profile features may be uniform, such as spacedevenly apart or forming a pattern. The spatial arrangement can berandom. Adjacent profile features can be about 10 to 500 nanometersapart, about 100 to 1000 nanometers apart, about 1 to 100 micrometersapart or about 5 to 100 micrometers apart. Adjacent profile features canoverlap one another or be adjacent one another so little or no flatregions are positioned there between. The desired spacing can depend, atleast in part, on the size and/or shape of the profile structures andthe desired structural color effect.

The profile features can have a certain cross-sectional shape (withrespect to a plane parallel the first plane). The textured surface canhave a plurality of profile features having the same or similarcross-sectional shape. The textured surface has a plurality of profilefeatures having a mixture of different cross-sectional shapes. Thecross-sectional shapes of the profile features can include polygonal(e.g., square or triangle or rectangle cross section), circular,semi-circular, tubular, oval, random, high and low aspect ratios,overlapping profile features, and the like.

The profile feature (e.g., about 10 nanometers to 500 micrometers) caninclude an upper, flat surface. The profile feature (e.g., about 10nanometers to 500 micrometers) can include an upper, concavely curvedsurface. The concave curved surface may extend symmetrically either sideof an uppermost point. The concave curved surface may extendsymmetrically across only 50 percent of the uppermost point. The profilefeature (e.g., about 10 nanometers to 500 micrometers) can include anupper, convexly curved surface. The curved surface may extendsymmetrically either side of an uppermost point. The curved surface mayextend symmetrically across only 50 percent of the uppermost point.

The profile feature can include protrusions from the textured surface.The profile feature can include indents (hollow areas) formed in thetextured surface. The profile feature can have a smooth, curved shape(e.g., a polygonal cross-section with curved corners).

The profile features (whether protrusions or depressions) can beapproximately conical or frusto-conical (i.e. the projections or indentsmay have horizontally or diagonally flattened tops) or have anapproximately part-spherical surface (e.g., a convex or concave surfacerespectively having a substantially even radius of curvature).

The profile features may have one or more sides or edges that extend ina direction that forms an angle to the first plane of the texturedsurface. The angle between the first plane and a side or edge of theprofile feature is about 45 degrees or less, about 30 degrees or less,about 25 degrees or less, or about 20 degrees or less. The one or moresides or edges may extend in a linear or planar orientation, or may becurved so that the angle changes as a function of distance from thefirst plane. The profile features may have one or more sides thatinclude step(s) and/or flat side(s). The profile feature can have one ormore sides (or portions thereof) that can be orthogonal or perpendicularto the first plane of the textured surface, or extend at an angle ofabout 10 degrees to 89 degrees to the first plane (90 degrees beingperpendicular or orthogonal to the first plane)). The profile featurecan have a side with a stepped configuration, where portions of the sidecan be parallel to the first plane of the textured surface or have anangle of about 1 degrees to 179 degrees (0 degrees being parallel to thefirst plane)).

The textured surface can have profile features with varying shapes(e.g., the profile features can vary in shape, height, width and lengthamong the profile features) or profile features with substantiallyuniform shapes and/or dimensions. The structural color produced by thetextured surface can be determined, at least in part, by the shape,dimensions, spacing, and the like, of the profile features.

The profile features can be shaped so as to result in a portion of thesurface (e.g., about 25 to 50 percent or more) being about normal to theincoming light when the light is incident at the normal to the firstplane of the textured surface. The profile features can be shaped so asto result in a portion of the surface (e.g., about 25 to 50 percent ormore) being about normal to the incoming light when the light isincident at an angle of up to 45 degrees to the first plane of thetextured surface.

The spatial orientation of the profile features on the textured surfacecan be used to produce the structural color, or to effect the degree towhich the structural color shifts at different viewing angles. Thespatial orientation of the profile features on the textured surface canbe random, a semi-random pattern, or in a set pattern. A set pattern ofprofile features is a known set up or configuration of profile featuresin a certain area (e.g., about 50 nanometers squared to about 10millimeters squared depending upon the dimensions of the profilefeatures (e.g., any increment between about 50 nanometers and about 10millimeters is included)). A semi-random pattern of profile features isa known set up of profile features in a certain area (e.g., about 50nanometers squared to 10 millimeters squared) with some deviation (e.g.,1 to 15% deviation from the set pattern), while random profile featuresare present in the area but the pattern of profile features isdiscernable. A random spatial orientation of the profile features in anarea produces no discernable pattern in a certain area, (e.g., about 50nanometers squared to 10 millimeters squared).

The spatial orientation of the profile features can be periodic (e.g.,full or partial) or non-periodic. A periodic spatial orientation of theprofile features is a recurring pattern at intervals. The periodicity ofthe periodic spatial orientation of the profile features can depend uponthe dimensions of the profile features but generally are periodic fromabout 50 nanometers to 100 micrometers. For example, when the dimensionsof the profile features are submicron, the periodicity of the periodicspatial orientation of the profile features can be in the 50 to 500nanometer range or 100 to 1000 nanometer range. In another example, whenthe dimensions of the profile features are at the micron level, theperiodicity of the periodic spatial orientation of the profile featurescan be in the 10 to 500 micrometer range or 10 to 1000 micrometer range.Full periodic pattern of profile features indicates that the entirepattern exhibits periodicity, whereas partial periodicity indicates thatless than all of the pattern exhibits periodicity (e.g., about 70-99percent of the periodicity is retained). A non-periodic spatialorientation of profile features is not periodic and does not showperiodicity based on the dimensions of the profile features, inparticular, no periodicity in the 50 to 500 nanometer range or 100 to1000 nanometer range where the dimensions are of the profile featuresare submicron or no periodicity in the 10 to 500 micrometer range or 10to 1000 micrometer range where the dimensions are of the profilefeatures are in the micron range.

In an aspect, the spatial orientation of the profile features on thetextured surface can be set to reduce distortion effects, e.g., causedby the interference of one profile feature with another in regard to thestructural color of the article. Since the shape, dimension, relativeorientation of the profile features can vary considerably across thetextured surface, the desired spacing and/or relative positioning for aparticular area (e.g., in the micrometer range or about 1 to 10 squaremicrometers) having profile features can be appropriately determined. Asdiscussed herein, the shape, dimension, relative orientation of theprofile features affect the contours of the reflective layer(s) and/orconstituent layer(s), so the dimensions (e.g., thickness), index ofrefraction, number of layers in the optical element (e.g., reflectivelayer(s) and constituent layer(s)) are considered when designing thetextured side of the texture layer.

The profile features are located in nearly random positions relative toone another across a specific area of the textured surface (e.g., in themicrometer range or about 1 to 10 square micrometers to centimeter rangeor about 0.5 to 5 square centimeters, and all range increments therein),where the randomness does not defeat the purpose of producing thestructural color. In other words, the randomness is consistent with thespacing, shape, dimension, and relative orientation of the profilefeatures, the dimensions (e.g., thickness), index of refraction, andnumber of layers (e.g., the reflective layer(s), the constituentlayer(s), and the like, with the goal to achieve the structural color.

The profile features are positioned in a set manner relative to oneanother across a specific area of the textured surface to achieve thepurpose of producing the structural color. The relative positions of theprofile features do not necessarily follow a pattern, but can follow apattern consistent with the desired structural color. As mentioned aboveand herein, various parameters related to the profile features, flatareas, and reflective layer(s) and/or the constituent layer can be usedto position the profile features in a set manner relative to oneanother.

The textured surface can include micro and/or nanoscale profile featuresthat can form gratings (e.g., a diffractive grating), photonic crystalstructure, a selective mirror structure, crystal fiber structures,deformed matrix structures, spiraled coiled structures, surface gratingstructures, and combinations thereof. The textured surface can includemicro and/or nanoscale profile features that form a grating having aperiodic or non-periodic design structure to impart the structuralcolor. The micro and/or nanoscale profile features can have apeak-valley pattern of profile features and/or flat areas to produce thedesired structural color. The grading can be an Echelette grating.

The profile features and the flat areas of the textured surface in theoptical element can appear as topographical undulations in each layer(e.g., reflective layer(s) and/or the constituent layer(s)). Forexample, referring to FIG. 2A, an optical element 200 includes atextured structure 220 having a plurality of profile features 222 andflat areas 224. As described herein, one or more of the profile features222 can be projections from a surface of the textured structure 220,and/or one or more of the profile features can be depressions in asurface of the textured structure 220 (not shown). One or moreconstituent layers 240 are disposed on the textured structure 220 andthen a reflective layer 230 and one or more constituent layers 245 aredisposed on the preceding layers. Adjacent layers (constituent layersand reflective layer) are made of different types of materials. In someembodiments, the resulting topography of the textured structure 220 andthe one or more constituent layers 240 and 245 and the reflective layer230 are not identical, but rather, the one or more constituent layers240 and 245 and the reflective layer 230 can have elevated or depressedregions 242 which are either elevated or depressed relative to theheight of the planar regions 244 and which roughly correspond to thelocation of the profile features 222 of the textured structure 220. Theone or more constituent layers 240 and 245 and the reflective layer 230have planar regions 244 that roughly correspond to the location of theflat areas 224 of the textured structure 220. Due to the presence of theelevated or depressed regions 242 and the planar regions 244, theresultant overall topography of the one or more constituent layers 240and 245 and the reflective layer 230 can be that of an undulating orwave-like structure. The dimension, shape, and spacing of the profilefeatures along with the number of layers of the constituent layer, thereflective layer, the thickness of each of the layers, refractive indexof each layer, and the type of material, can be used to produce anoptical element which results in a particular structural color.

While the textured surface can produce the structural color in someembodiments, or can affect the degree to which the structural colorshifts at different viewing angles, in other embodiments, a “texturedsurface” or surface with texture may not produce the structural color,or may not affect the degree to which the structural color shifts atdifferent viewing angles. The structural color can be produced by thedesign of the optical element with or without the textured surface. As aresult, the optical element can include the textured surface havingprofile elements of dimensions in the nanometer to millimeter range, butthe structural color or the shifting of the structural color is notattributable to the presence or absence of the textured surface. Inother words, the optical element imparts the same structural color whereor not the textured surface is present The design of the texturedsurface can be configured to not affect the structural color imparted bythe optical element, or not affect the shifting of the structural colorimparted by the optical element. The shape of the profile features,dimensions of the shapes, the spatial orientation of the profilefeatures relative to one another, and the like can be selected so thatthe textured surface does not affect the structural color attributableto the optical element.

In another embodiment, the structural color can be imparted by theoptical element without the textured surface. The surface of the layersof the optical element are substantially flat (or substantially threedimensional flat planar surface) or flat (or three dimensional flatplanar surface) at the microscale (e.g., about 1 to 500 micrometers)and/or nanoscale (e.g., about 50 to 500 nanometers). In regard tosubstantially flat or substantially planar the surface can include someminor topographical features (e.g., nanoscale and/or microscale) such asthose that might be caused due to unintentional imperfections, slightundulations that are unintentional, other topographical features (e.g.,extensions above the plane of the layer or depressions below or into theplane of the layer) caused by the equipment and/or process used and thelike that are unintentionally introduced. The topographical features donot resemble profile features of the textured surface. In addition, thesubstantially flat (or substantially three dimensional flat planarsurface) or flat (or three dimensional flat planar surface) may includecurvature as the dimensions of the optical element increase, for exampleabout 500 micrometers or more, about 10 millimeter or more, about 10centimeters or more, depending upon the dimensions of the opticalelement, as long as the surface is flat or substantially flat and thesurface only includes some minor topographical features.

FIG. 2B is a cross-section illustration of a substantially flat (orsubstantially three-dimensional flat planar surface) or flat (orthree-dimensional flat planar surface) optical element 300. The opticalelement 300 includes one or more constituent layers 340 are disposed onthe flat or three-dimensional flat planar surface structure 320 and thena reflective layer 330 and one or more constituent layers 345 aredisposed on the preceding layers. Adjacent layers (constituent layersand reflective layer) are made of different types of materials. Thematerial that makes up the constituent layers and the reflective layer,number of layers of the constituent layer, the reflective layer, thethickness of each of the layers, refractive index of each layer, and thelike, can produce an optical element which results in a particularstructural color.

Additional details are provided regarding the polymeric materialsreferenced herein for example, the polymers described in reference tothe article, components of the article, structures, layers, films,bladders, foams, coating, and like the. The polymer can be a thermosetpolymer or a thermoplastic polymer. The polymer can be an elastomericpolymer, including an elastomeric thermoset polymer or an elastomericthermoplastic polymer. The polymer can be selected from: polyurethanes(including elastomeric polyurethanes, thermoplastic polyurethanes(TPUs), and elastomeric TPUs), polyesters, polyethers, polyamides, vinylpolymers (e.g., copolymers of vinyl alcohol, vinyl esters, ethylene,acrylates, methacrylates, styrene, and so on), polyacrylonitriles,polyphenylene ethers, polycarbonates, polyureas, polystyrenes,co-polymers thereof (including polyester-polyurethanes,polyether-polyurethanes, polycarbonate-polyurethanes, polyether blockpolyamides (PEBAs), and styrene block copolymers), and any combinationthereof, as described herein. The polymer can include one or morepolymers selected from the group consisting of polyesters, polyethers,polyamides, polyurethanes, polyolefins copolymers of each, andcombinations thereof.

The term “polymer” refers to a chemical compound formed of a pluralityof repeating structural units referred to as monomers. Polymers oftenare formed by a polymerization reaction in which the plurality ofstructural units become covalently bonded together. When the monomerunits forming the polymer all have the same chemical structure, thepolymer is a homopolymer. When the polymer includes two or more monomerunits having different chemical structures, the polymer is a copolymer.One example of a type of copolymer is a terpolymer, which includes threedifferent types of monomer units. The co-polymer can include two or moredifferent monomers randomly distributed in the polymer (e.g., a randomco-polymer). Alternatively, one or more blocks containing a plurality ofa first type of monomer can be bonded to one or more blocks containing aplurality of a second type of monomer, forming a block copolymer. Asingle monomer unit can include one or more different chemicalfunctional groups.

Polymers having repeating units which include two or more types ofchemical functional groups can be referred to as having two or moresegments. For example, a polymer having repeating units of the samechemical structure can be referred to as having repeating segments.Segments are commonly described as being relatively harder or softerbased on their chemical structures, and it is common for polymers toinclude relatively harder segments and relatively softer segments bondedto each other in a single monomeric unit or in different monomericunits. When the polymer includes repeating segments, physicalinteractions or chemical bonds can be present within the segments orbetween the segments or both within and between the segments. Examplesof segments often referred to as hard segments include segmentsincluding a urethane linkage, which can be formed from reacting anisocyanate with a polyol to form a polyurethane. Examples of segmentsoften referred to as soft segments include segments including an alkoxyfunctional group, such as segments including ether or ester functionalgroups, and polyester segments. Segments can be referred to based on thename of the functional group present in the segment (e.g., a polyethersegment, a polyester segment), as well as based on the name of thechemical structure which was reacted in order to form the segment (e.g.,a polyol-derived segment, an isocyanate-derived segment). When referringto segments of a particular functional group or of a particular chemicalstructure from which the segment was derived, it is understood that thepolymer can contain up to 10 mole percent of segments of otherfunctional groups or derived from other chemical structures. Forexample, as used herein, a polyether segment is understood to include upto 10 mole percent of non-polyether segments.

As previously described, the polymer can be a thermoplastic polymer. Ingeneral, a thermoplastic polymer softens or melts when heated andreturns to a solid state when cooled. The thermoplastic polymertransitions from a solid state to a softened state when its temperatureis increased to a temperature at or above its softening temperature, anda liquid state when its temperature is increased to a temperature at orabove its melting temperature. When sufficiently cooled, thethermoplastic polymer transitions from the softened or liquid state tothe solid state. As such, the thermoplastic polymer may be softened ormelted, molded, cooled, re-softened or re-melted, re-molded, and cooledagain through multiple cycles. For amorphous thermoplastic polymers, thesolid state is understood to be the “rubbery” state above the glasstransition temperature of the polymer. The thermoplastic polymer canhave a melting temperature from about 90 degrees C. to about 190 degreesC. when determined in accordance with ASTM D3418-97 as described hereinbelow, and includes all subranges therein in increments of 1 degree. Thethermoplastic polymer can have a melting temperature from about 93degrees C. to about 99 degrees C. when determined in accordance withASTM D3418-97 as described herein below. The thermoplastic polymer canhave a melting temperature from about 112 degrees C. to about 118degrees C. when determined in accordance with ASTM D3418-97 as describedherein below.

The glass transition temperature is the temperature at which anamorphous polymer transitions from a relatively brittle “glassy” stateto a relatively more flexible “rubbery” state. The thermoplastic polymercan have a glass transition temperature from about −20 degrees C. toabout 30 degrees C. when determined in accordance with ASTM D3418-97 asdescribed herein below. The thermoplastic polymer can have a glasstransition temperature (from about −13 degree C. to about −7 degrees C.when determined in accordance with ASTM D3418-97 as described hereinbelow. The thermoplastic polymer can have a glass transition temperaturefrom about 17 degrees C. to about 23 degrees C. when determined inaccordance with ASTM D3418-97 as described herein below.

The thermoplastic polymer can have a melt flow index from about 10 toabout 30 cubic centimeters per 10 minutes (cm3/10 min) when tested inaccordance with ASTM D1238-13 as described herein below at 160 degreesC. using a weight of 2.16 kilograms (kg). The thermoplastic polymer canhave a melt flow index from about 22 cm3/10 min to about 28 cm3/10 minwhen tested in accordance with ASTM D1238-13 as described herein belowat 160 degrees C. using a weight of 2.16 kg.

The thermoplastic polymer can have a cold Ross flex test result of about120,000 to about 180,000 cycles without cracking or whitening whentested on a thermoformed plaque of the thermoplastic polymer inaccordance with the cold Ross flex test as described herein below. Thethermoplastic polymer can have a cold Ross flex test result of about140,000 to about 160,000 cycles without cracking or whitening whentested on a thermoformed plaque of the thermoplastic polymer inaccordance with the cold Ross flex test as described herein below.

The thermoplastic polymer can have a modulus from about 5 megaPascals(MPa) to about 100 MPa when determined on a thermoformed plaque inaccordance with ASTM D412-98 Standard Test Methods for Vulcanized Rubberand Thermoplastic Rubbers and Thermoplastic Elastomers-Tension withmodifications described herein below. The thermoplastic polymer can havea modulus from about 20 MPa to about 80 MPa when determined on athermoformed plaque in accordance with ASTM D412-98 Standard TestMethods for Vulcanized Rubber and Thermoplastic Rubbers andThermoplastic Elastomers-Tension with modifications described hereinbelow.

The polymer can be a thermoset polymer. As used herein, a “thermosetpolymer” is understood to refer to a polymer which cannot be heated andmelted, as its melting temperature is at or above its decompositiontemperature. A “thermoset material” refers to a material which comprisesat least one thermoset polymer. The thermoset polymer and/or thermosetmaterial can be prepared from a precursor (e.g., an uncured or partiallycured polymer or material) using thermal energy and/or actinic radiation(e.g., ultraviolet radiation, visible radiation, high energy radiation,infrared radiation) to form a partially cured or fully cured polymer ormaterial which no longer remains fully thermoplastic. In some cases, thecured or partially cured polymer or material may remain thermoelasticproperties, in that it is possible to partially soften and mold thepolymer or material at elevated temperatures and/or pressures, but it isnot possible to melt the polymer or material. The curing can bepromoted, for example, with the use of high pressure and/or a catalyst.In many examples, the curing process is irreversible since it results incross-linking and/or polymerization reactions of the precursors. Theuncured or partially cured polymers or materials can be malleable orliquid prior to curing. In some cases, the uncured or partially curedpolymers or materials can be molded into their final shape, or used asadhesives. Once hardened, a thermoset polymer or material cannot bere-melted in order to be reshaped. The textured surface can be formed bypartially or fully curing an uncured precursor material to lock in thetextured surface.

Polyurethane

The polymer can be a polyurethane, such as a thermoplastic polyurethane(also referred to as “TPU”). Alternatively, the polymer can be athermoset polyurethane. Additionally, polyurethane can be an elastomericpolyurethane, including an elastomeric TPU or an elastomeric thermosetpolyurethane. The elastomeric polyurethane can include hard and softsegments. The hard segments can comprise or consist of urethane segments(e.g., isocyanate-derived segments). The soft segments can comprise orconsist of alkoxy segments (e.g., polyol-derived segments includingpolyether segments, or polyester segments, or a combination of polyethersegments and polyester segments). The polyurethane can comprise orconsist essentially of an elastomeric polyurethane having repeating hardsegments and repeating soft segments.

One or more of the polyurethanes can be produced by polymerizing one ormore isocyanates with one or more polyols to produce polymer chainshaving carbamate linkages. The portions of the polyurethane polymerchain formed by the segments derived from isocyanates can be referred toas the hard segments, while the portions derived from polyols can bereferred to as soft segments. Optionally, the isocyanates can also bechain extended with one or more chain extenders to bridge two or moreisocyanates, increasing the length of the hard segments.

Examples of suitable aliphatic diisocyanates for producing thepolyurethane polymer chains include hexamethylene diisocyanate (HDI),isophorone diisocyanate (IPDI), butylenediisocyanate (BDI),bisisocyanatocyclohexylmethane (HMDI), 2,2,4-trimethylhexamethylenediisocyanate (TMDI), bisisocyanatomethylcyclohexane,bisisocyanatomethyltricyclodecane, norbornane diisocyanate (NDI),cyclohexane diisocyanate (CHDI), 4,4′-dicyclohexylmethane diisocyanate(H12MDI), diisocyanatododecane, lysine diisocyanate, and combinationsthereof.

The isocyanate-derived segments can include segments derived fromaliphatic diisocyanate. A majority of the isocyanate-derived segmentscan comprise segments derived from aliphatic diisocyanates. At least 90%of the isocyanate-derived segments are derived from aliphaticdiisocyanates. The isocyanate-derived segments can consist essentiallyof segments derived from aliphatic diisocyanates. The aliphaticdiisocyanate-derived segments can be derived substantially (e.g., about50 percent or more, about 60 percent or more, about 70 percent or more,about 80 percent or more, about 90 percent or more) from linearaliphatic diisocyanates. At least 80% of the aliphaticdiisocyanate-derived segments can be derived from aliphaticdiisocyanates that are free of side chains. The segments derived fromaliphatic diisocyanates can include linear aliphatic diisocyanateshaving from 2 to 10 carbon atoms.

Examples of suitable aromatic diisocyanates for producing thepolyurethane polymer chains include toluene diisocyanate (TDI), TDIadducts with trimethyloylpropane (TMP), methylene diphenyl diisocyanate(MDI), xylene diisocyanate (XDI), tetramethylxylylene diisocyanate(TMXDI), hydrogenated xylene diisocyanate (HXDI), naphthalene1,5-diisocyanate (NDI), 1,5-tetrahydronaphthalene diisocyanate,para-phenylene diisocyanate (PPDI), 3,3′-dimethyldiphenyl-4,4′-diisocyanate (DDDI), 4,4′-dibenzyl diisocyanate (DBDI),4-chloro-1,3-phenylene diisocyanate, and combinations thereof. Thepolymer chains can be substantially free of aromatic groups.

The polyurethane polymer chains can be produced from diisocyanatesincluding HMDI, TDI, MDI, H12 aliphatics, and combinations thereof. Forexample, the polyurethane can comprise one or more polyurethane polymerchains produced from diisocyanates including HMDI, TDI, MDI, H12aliphatics, and combinations thereof.

Polyurethane chains which are at least partially crosslinked or whichcan be crosslinked, can be used in accordance with the presentdisclosure. It is possible to produce crosslinked or crosslinkablepolyurethane chains by reacting multi-functional isocyanates to form thepolyurethane. Examples of suitable triisocyanates for producing thepolyurethane chains include TDI, HDI, and IPDI adducts withtrimethyloylpropane (TMP), uretdiones (i.e., dimerized isocyanates),polymeric MDI, and combinations thereof.

Polyamides

The polymer can comprise a polyamide, such as a thermoplastic polyamide,or a thermoset polyamide. The polyamide can be an elastomeric polyamide,including an elastomeric thermoplastic polyamide or an elastomericthermoset polyamide. The polyamide can be a polyamide homopolymer havingrepeating polyamide segments of the same chemical structure.Alternatively, the polyamide can comprise a number of polyamide segmentshaving different polyamide chemical structures (e.g., polyamide 6segments, polyamide 11 segments, polyamide 12 segments, polyamide 66segments, etc.). The polyamide segments having different chemicalstructure can be arranged randomly, or can be arranged as repeatingblocks.

The polyamide can be a co-polyamide (i.e., a co-polymer includingpolyamide segments and non-polyamide segments). The polyamide segmentsof the co-polyamide can comprise or consist of polyamide 6 segments,polyamide 11 segments, polyamide 12 segments, polyamide 66 segments, orany combination thereof. The polyamide segments of the co-polyamide canbe arranged randomly, or can be arranged as repeating segments. Thepolyamide segments can comprise or consist of polyamide 6 segments, orpolyamide 12 segments, or both polyamide 6 segment and polyamide 12segments. In the example where the polyamide segments of theco-polyamide include of polyamide 6 segments and polyamide 12 segments,the segments can be arranged randomly. The non-polyamide segments of theco-polyamide can comprise or consist of polyether segments, polyestersegments, or both polyether segments and polyester segments. Theco-polyamide can be a block co-polyamide, or can be a randomco-polyamide. The copolyamide can be formed from the polycondensation ofa polyamide oligomer or prepolymer with a second oligomer prepolymer toform a copolyamide (i.e., a co-polymer including polyamide segments.Optionally, the second prepolymer can be a hydrophilic prepolymer.

The polyamide can be a polyamide-containing block co-polymer. Forexample, the block co-polymer can have repeating hard segments, andrepeating soft segments. The hard segments can comprise polyamidesegments, and the soft segments can comprise non-polyamide segments. Thepolyamide-containing block co-polymer can be an elastomeric co-polyamidecomprising or consisting of polyamide-containing block co-polymershaving repeating hard segments and repeating soft segments. In blockco-polymers, including block co-polymers having repeating hard segmentsand soft segments, physical crosslinks can be present within thesegments or between the segments or both within and between thesegments.

The polyamide itself, or the polyamide segment of thepolyamide-containing block co-polymer can be derived from thecondensation of polyamide prepolymers, such as lactams, amino acids,and/or diamino compounds with dicarboxylic acids, or activated formsthereof. The resulting polyamide segments include amide linkages(—(CO)NH—). The term “amino acid” refers to a molecule having at leastone amino group and at least one carboxyl group. Each polyamide segmentof the polyamide can be the same or different.

The polyamide or the polyamide segment of the polyamide-containing blockco-polymer can be derived from the polycondensation of lactams and/oramino acids.

The polyamide can be a thermoplastic polyamide and the constituents ofthe polyamide block and their proportion can be chosen in order toobtain a melting temperature of less than 150 degrees C., such as amelting point of from about 90 degrees C. to about 135 degrees C. Thevarious constituents of the thermoplastic polyamide block and theirproportion can be chosen in order to obtain a melting point of less than150 degrees C., such as from about and 90 degrees C. to about 135degrees C.

Exemplary commercially available copolymers include, but are not limitedto, those available under the tradenames of “VESTAMID” (EvonikIndustries, Essen, Germany); “PLATAMID” (Arkema, Colombes, France),e.g., product code H2694; “PEBAX” (Arkema), e.g., product code “PEBAXMH1657” and “PEBAX MV1074”; “PEBAX RNEW” (Arkema); “GRILAMID”(EMS-Chemie AG, Domat-Ems, Switzerland), or also to other similarmaterials produced by various other suppliers.

The polyamide can be physically crosslinked through, e.g., nonpolar orpolar interactions between the polyamide groups of the polymers. Inexamples where the polyamide is a copolyamide, the copolyamide can bephysically crosslinked through interactions between the polyamidegroups, and optionally by interactions between the copolymer groups.When the co-polyamide is physically crosslinked through interactionsbetween the polyamide groups, the polyamide segments can form theportion of the polymer referred to as the hard segment, and copolymersegments can form the portion of the polymer referred to as the softsegment. For example, when the copolyamide is a poly(ether-block-amide),the polyamide segments form the hard segments of the polymer, andpolyether segments form the soft segments of the polymer. Therefore, insome examples, the polymer can include a physically crosslinkedpolymeric network having one or more polymer chains with amide linkages.

The polyamide segment of the co-polyamide can include polyamide-11 orpolyamide-12 and the polyether segment can be a segment selected fromthe group consisting of polyethylene oxide, polypropylene oxide, andpolytetramethylene oxide segments, and combinations thereof.

The polyamide can be partially or fully covalently crosslinked, aspreviously described herein. In some cases, the degree of crosslinkingpresent in the polyamide is such that, when it is thermally processed,e.g., in the form of a yarn or fiber to form the articles of the presentdisclosure, the partially covalently crosslinked thermoplastic polyamideretains sufficient thermoplastic character that the partially covalentlycrosslinked thermoplastic polyamide is melted during the processing andre-solidifies. In other cases, the crosslinked polyamide is a thermosetpolymer.

Polyesters

The polymers can comprise a polyester. The polyester can comprise athermoplastic polyester, or a thermoset polyester. Additionally, thepolyester can be an elastomeric polyester, including a thermoplasticpolyester or a thermoset elastomeric polyester. The polyester can beformed by reaction of one or more carboxylic acids, or its ester-formingderivatives, with one or more bivalent or multivalent aliphatic,alicyclic, aromatic or araliphatic alcohols or a bisphenol. Thepolyester can be a polyester homopolymer having repeating polyestersegments of the same chemical structure. Alternatively, the polyestercan comprise a number of polyester segments having different polyesterchemical structures (e.g., polyglycolic acid segments, polylactic acidsegments, polycaprolactone segments, polyhydroxyalkanoate segments,polyhydroxybutyrate segments, etc.). The polyester segments havingdifferent chemical structure can be arranged randomly, or can bearranged as repeating blocks.

Exemplary carboxylic acids that can be used to prepare a polyesterinclude, but are not limited to, adipic acid, pimelic acid, subericacid, azelaic acid, sebacic acid, nonane dicarboxylic acid, decanedicarboxylic acid, undecane dicarboxylic acid, terephthalic acid,isophthalic acid, alkyl-substituted or halogenated terephthalic acid,alkyl-substituted or halogenated isophthalic acid, nitro-terephthalicacid, 4,4′-diphenyl ether dicarboxylic acid, 4,4′-diphenyl thioetherdicarboxylic acid, 4,4′-diphenyl sulfone-dicarboxylic acid,4,4′-diphenyl alkylenedicarboxylic acid, naphthalene-2,6-dicarboxylicacid, cyclohexane-1,4-dicarboxylic acid and cyclohexane-1,3-dicarboxylicacid. Exemplary diols or phenols suitable for the preparation of thepolyester include, but are not limited to, ethylene glycol, diethyleneglycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol,1,10-decanediol, 1,2-propanediol, 2,2-dimethyl-1,3-propanediol,2,2,4-trimethylhexanediol, p-xylenediol, 1,4-cyclohexanediol,1,4-cyclohexane dimethanol, and bis-phenol A.

The polyester can be a polybutylene terephthalate (PBT), apolytrimethylene terephthalate, a polyhexamethylene terephthalate, apoly-1,4-dimethylcyclohexane terephthalate, a polyethylene terephthalate(PET), a polyethylene isophthalate (PEI), a polyarylate (PAR), apolybutylene naphthalate (PBN), a liquid crystal polyester, or a blendor mixture of two or more of the foregoing.

The polyester can be a co-polyester (i.e., a co-polymer includingpolyester segments and non-polyester segments). The co-polyester can bean aliphatic co-polyester (i.e., a co-polyester in which both thepolyester segments and the non-polyester segments are aliphatic).Alternatively, the co-polyester can include aromatic segments. Thepolyester segments of the co-polyester can comprise or consistessentially of polyglycolic acid segments, polylactic acid segments,polycaprolactone segments, polyhydroxyalkanoate segments,polyhydroxybutyrate segments, or any combination thereof. The polyestersegments of the co-polyester can be arranged randomly, or can bearranged as repeating blocks.

For example, the polyester can be a block co-polyester having repeatingblocks of polymeric units of the same chemical structure which arerelatively harder (hard segments), and repeating blocks of the samechemical structure which are relatively softer (soft segments). In blockco-polyesters, including block co-polyesters having repeating hardsegments and soft segments, physical crosslinks can be present withinthe blocks or between the blocks or both within and between the blocks.The polymer can comprise or consist essentially of an elastomericco-polyester having repeating blocks of hard segments and repeatingblocks of soft segments.

The non-polyester segments of the co-polyester can comprise or consistessentially of polyether segments, polyamide segments, or both polyethersegments and polyamide segments. The co-polyester can be a blockco-polyester, or can be a random co-polyester. The co-polyester can beformed from the polycondensation of a polyester oligomer or prepolymerwith a second oligomer prepolymer to form a block copolyester.Optionally, the second prepolymer can be a hydrophilic prepolymer. Forexample, the co-polyester can be formed from the polycondensation ofterephthalic acid or naphthalene dicarboxylic acid with ethylene glycol,1,4-butanediol, or 1,3-propanediol. Examples of co-polyesters includepolyethylene adipate, polybutylene succinate,poly(3-hydroxbutyrate-co-3-hydroxyvalerate), polyethylene terephthalate,polybutylene terephthalate, polytrimethylene terephthalate, polyethylenenapthalate, and combinations thereof. The co-polyamide can comprise orconsist of polyethylene terephthalate.

The polyester can be a block copolymer comprising segments of one ormore of polybutylene terephthalate (PBT), a polytrimethyleneterephthalate, a polyhexamethylene terephthalate, apoly-1,4-dimethylcyclohexane terephthalate, a polyethylene terephthalate(PET), a polyethylene isophthalate (PEI), a polyarylate (PAR), apolybutylene naphthalate (PBN), and a liquid crystal polyester. Forexample, a suitable polyester that is a block copolymer can be a PET/PEIcopolymer, a polybutylene terephthalate/tetraethylene glycol copolymer,a polyoxyalkylenediimide diacid/polybutylene terephthalate copolymer, ora blend or mixture of any of the foregoing.

Polyolefins

The polymers can comprise or consist essentially of a polyolefin. Thepolyolefin can be a thermoplastic polyolefin or a thermoset polyolefin.Additionally, the polyolefin can be an elastomeric polyolefin, includinga thermoplastic elastomeric polyolefin or a thermoset elastomericpolyolefin. Exemplary polyolefins can include polyethylene,polypropylene, and olefin elastomers (e.g., metallocene-catalyzed blockcopolymers of ethylene and α-olefins having 4 to about 8 carbon atoms).The polyolefin can be a polymer comprising a polyethylene, anethylene-α-olefin copolymer, an ethylene-propylene rubber (EPDM), apolybutene, a polyisobutylene, a poly-4-methylpent-1-ene, apolyisoprene, a polybutadiene, a ethylene-methacrylic acid copolymer,and an olefin elastomer such as a dynamically cross-linked polymerobtained from polypropylene (PP) and an ethylene-propylene rubber(EPDM), and blends or mixtures of the foregoing. Further exemplarypolyolefins include polymers of cycloolefins such as cyclopentene ornorbornene.

It is to be understood that polyethylene, which optionally can becrosslinked, is inclusive a variety of polyethylenes, including lowdensity polyethylene (LDPE), linear low density polyethylene (LLDPE),(VLDPE) and (ULDPE), medium density polyethylene (MDPE), high densitypolyethylene (HDPE), high density and high molecular weight polyethylene(HDPE-HMW), high density and ultrahigh molecular weight polyethylene(HDPE-UHMW), and blends or mixtures of any the foregoing polyethylenes.A polyethylene can also be a polyethylene copolymer derived frommonomers of monolefins and diolefins copolymerized with a vinyl, acrylicacid, methacrylic acid, ethyl acrylate, vinyl alcohol, and/or vinylacetate. Polyolefin copolymers comprising vinyl acetate-derived unitscan be a high vinyl acetate content copolymer, e.g., greater than about50 weight percent vinyl acetate-derived composition.

The polyolefin can be a mixture of polyolefins, such as a mixture of twoor more polyolefins disclosed herein above. For example, a suitablemixture of polyolefins can be a mixture of polypropylene withpolyisobutylene, polypropylene with polyethylene (for example PP/HDPE,PP/LDPE) or mixtures of different types of polyethylene (for exampleLDPE/HDPE).

The polyolefin can be a copolymer of suitable monolefin monomers or acopolymer of a suitable monolefin monomer and a vinyl monomer. Exemplarypolyolefin copolymers include ethylene/propylene copolymers, linear lowdensity polyethylene (LLDPE) and mixtures thereof with low densitypolyethylene (LDPE), propylene/but-1-ene copolymers,propylene/isobutylene copolymers, ethylene/but-1-ene copolymers,ethylene/hexene copolymers, ethylene/methylpentene copolymers,ethylene/heptene copolymers, ethylene/octene copolymers,propylene/butadiene copolymers, isobutylene/isoprene copolymers,ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylatecopolymers, ethylene/vinyl acetate copolymers and their copolymers withcarbon monoxide or ethylene/acrylic acid copolymers and their salts(ionomers) as well as terpolymers of ethylene with propylene and a dienesuch as hexadiene, dicyclopentadiene or ethylidene-norbornene; andmixtures of such copolymers with one another and with polymers mentionedin 1) above, for example polypropylene/ethylene-propylene copolymers,LDPE/ethylene-vinyl acetate copolymers (EVA), LDPE/ethylene-acrylic acidcopolymers (EAA), LLDPE/EVA, LLDPE/EAA and alternating or randompolyalkylene/carbon monoxide copolymers and mixtures thereof with otherpolymers, for example polyamides.

The polyolefin can be a polypropylene homopolymer, a polypropylenecopolymers, a polypropylene random copolymer, a polypropylene blockcopolymer, a polyethylene homopolymer, a polyethylene random copolymer,a polyethylene block copolymer, a low density polyethylene (LDPE), alinear low density polyethylene (LLDPE), a medium density polyethylene,a high density polyethylene (HDPE), or blends or mixtures of one or moreof the preceding polymers.

The polyolefin can be a polypropylene. The term “polypropylene,” as usedherein, is intended to encompass any polymeric composition comprisingpropylene monomers, either alone or in mixture or copolymer with otherrandomly selected and oriented polyolefins, dienes, or other monomers(such as ethylene, butylene, and the like). Such a term also encompassesany different configuration and arrangement of the constituent monomers(such as atactic, syndiotactic, isotactic, and the like). Thus, the termas applied to fibers is intended to encompass actual long strands,tapes, threads, and the like, of drawn polymer. The polypropylene can beof any standard melt flow (by testing); however, standard fiber gradepolypropylene resins possess ranges of Melt Flow Indices between about 1and 1000.

The polyolefin can be a polyethylene. The term “polyethylene,” as usedherein, is intended to encompass any polymeric composition comprisingethylene monomers, either alone or in mixture or copolymer with otherrandomly selected and oriented polyolefins, dienes, or other monomers(such as propylene, butylene, and the like). Such a term alsoencompasses any different configuration and arrangement of theconstituent monomers (such as atactic, syndiotactic, isotactic, and thelike). Thus, the term as applied to fibers is intended to encompassactual long strands, tapes, threads, and the like, of drawn polymer. Thepolyethylene can be of any standard melt flow (by testing); however,standard fiber grade polyethylene resins possess ranges of Melt FlowIndices between about 1 and 1000.

The thermoplastic and/or thermosetting material can further comprise oneor more processing aids. The processing aid can be a non-polymericmaterial. These processing aids can be independently selected from thegroup including, but not limited to, curing agents, initiators,plasticizers, mold release agents, lubricants, antioxidants, flameretardants, dyes, pigments, reinforcing and non-reinforcing fillers,fiber reinforcements, and light stabilizers.

In articles that include a textile, the optical element can be disposedonto the textile (e.g., the optical element is likely in the “on itsside” configuration unless the textile is thin or otherwise the firstside of the optical element can be illuminated). The textile or at leastan outer layer of the textile can includes a thermoplastic material thatthe optical element can disposed onto. The textile can be a nonwoventextile, a synthetic leather, a knit textile, or a woven textile. Thetextile can comprise a first fiber or a first yarn, where the firstfiber or the first yarn can include at least an outer layer formed ofthe first thermoplastic material. A region of the first or second sideof the structure onto which the optical element is disposed can includethe first fiber or the first yarn in a non-filamentous conformation. Theoptical element can be disposed onto the textile or the textile can beprocessed so that the optical element can be disposed onto the textile.The textured surface can be made of or formed from the textile surface.The textile surface can be used to form the textured surface, and eitherbefore or after this, the optical element can be applied to the textile.

A “textile” may be defined as any material manufactured from fibers,filaments, or yarns characterized by flexibility, fineness, and a highratio of length to thickness. Textiles generally fall into twocategories. The first category includes textiles produced directly fromwebs of filaments or fibers by randomly interlocking to constructnon-woven fabrics and felts. The second category includes textilesformed through a mechanical manipulation of yarn, thereby producing awoven fabric, a knitted fabric, a braided fabric, a crocheted fabric,and the like.

The terms “filament,” “fiber,” or “fibers” as used herein refer tomaterials that are in the form of discrete elongated pieces that aresignificantly longer than they are wide. The fiber can include natural,manmade or synthetic fibers. The fibers may be produced by conventionaltechniques, such as extrusion, electrospinning, interfacialpolymerization, pulling, and the like. The fibers can include carbonfibers, boron fibers, silicon carbide fibers, titania fibers, aluminafibers, quartz fibers, glass fibers, such as E, A, C, ECR, R, S, D, andNE glasses and quartz, or the like. The fibers can be fibers formed fromsynthetic polymers capable of forming fibers such as poly(ether ketone),polyimide, polybenzoxazole, poly(phenylene sulfide), polyesters,polyolefins (e.g., polyethylene, polypropylene), aromatic polyamides(e.g., an aramid polymer such as para-aramid fibers and meta-aramidfibers), aromatic polyimides, polybenzimidazoles, polyetherimides,polytetrafluoroethylene, acrylic, modacrylic, poly(vinyl alcohol),polyamides, polyurethanes, and copolymers such as polyether-polyureacopolymers, polyester-polyurethanes, polyether block amide copolymers,or the like. The fibers can be natural fibers (e.g., silk, wool,cashmere, vicuna, cotton, flax, hemp, jute, sisal). The fibers can beman-made fibers from regenerated natural polymers, such as rayon,lyocell, acetate, triacetate, rubber, and poly(lactic acid).

The fibers can have an indefinite length. For example, man-made andsynthetic fibers are generally extruded in substantially continuousstrands. Alternatively, the fibers can be staple fibers, such as, forexample, cotton fibers or extruded synthetic polymer fibers can be cutto form staple fibers of relatively uniform length. The staple fiber canhave a have a length of about 1 millimeter to 100 centimeters or more aswell as any increment therein (e.g., 1 millimeter increments).

The fiber can have any of a variety of cross-sectional shapes. Naturalfibers can have a natural cross-section, or can have a modifiedcross-sectional shape (e.g., with processes such as mercerization).Man-made or synthetic fibers can be extruded to provide a strand havinga predetermined cross-sectional shape. The cross-sectional shape of afiber can affect its properties, such as its softness, luster, andwicking ability. The fibers can have round or essentially round crosssections. Alternatively, the fibers can have non-round cross sections,such as flat, oval, octagonal, rectangular, wedge-shaped, triangular,dog-bone, multi-lobal, multi-channel, hollow, core-shell, or othershapes.

The fiber can be processed. For example, the properties of fibers can beaffected, at least in part, by processes such as drawing (stretching)the fibers, annealing (hardening) the fibers, and/or crimping ortexturizing the fibers.

In some cases a fiber can be a multi-component fiber, such as onecomprising two or more co-extruded polymeric materials. The two or moreco-extruded polymeric materials can be extruded in a core-sheath,islands-in-the-sea, segmented-pie, striped, or side-by-sideconfiguration. A multi-component fiber can be processed in order to forma plurality of smaller fibers (e.g., microfibers) from a single fiber,for example, by remove a sacrificial material.

The fiber can be a carbon fiber such as TARIFYL produced by FormosaPlastics Corp. of Kaohsiung City, Taiwan, (e.g., 12,000, 24,000, and48,000 fiber tows, specifically fiber types TC-35 and TC-35R), carbonfiber produced by SGL Group of Wiesbaden, Germany (e.g., 50,000 fibertow), carbon fiber produced by Hyosung of Seoul, South Korea, carbonfiber produced by Toho Tenax of Tokyo, Japan, fiberglass produced byJushi Group Co., LTD of Zhejiang, China (e.g., E6, 318, silane-basedsizing, filament diameters 14, 15, 17, 21, and 24 micrometers), andpolyester fibers produced by Amann Group of Bonningheim, Germany (e.g.,SERAFILE 200/2 non-lubricated polyester filament and SERAFILE COMPHIL200/2 lubricated polyester filament).

A plurality of fibers includes 2 to hundreds or thousands or morefibers. The plurality of fibers can be in the form of bundles of strandsof fibers, referred to as tows, or in the form of relatively alignedstaple fibers referred to as sliver and roving. A single type fiber canbe used either alone or in combination with one or more different typesof fibers by co-mingling two or more types of fibers. Examples ofco-mingled fibers include polyester fibers with cotton fibers, glassfibers with carbon fibers, carbon fibers with aromatic polyimide(aramid) fibers, and aromatic polyimide fibers with glass fibers.

As used herein, the term “yarn” refers to an assembly formed of one ormore fibers, wherein the strand has a substantial length and arelatively small cross-section, and is suitable for use in theproduction of textiles by hand or by machine, including textiles madeusing weaving, knitting, crocheting, braiding, sewing, embroidery, orropemaking techniques. Thread is a type of yarn commonly used forsewing.

Yarns can be made using fibers formed of natural, man-made and syntheticmaterials. Synthetic fibers are most commonly used to make spun yarnsfrom staple fibers, and filament yarns. Spun yarn is made by arrangingand twisting staple fibers together to make a cohesive strand. Theprocess of forming a yarn from staple fibers typically includes cardingand drawing the fibers to form sliver, drawing out and twisting thesliver to form roving, and spinning the roving to form a strand.Multiple strands can be plied (twisted together) to make a thicker yarn.The twist direction of the staple fibers and of the plies can affect thefinal properties of the yarn. A filament yarn can be formed of a singlelong, substantially continuous filament, which is conventionallyreferred to as a “monofilament yarn,” or a plurality of individualfilaments grouped together. A filament yarn can also be formed of two ormore long, substantially continuous filaments which are grouped togetherby grouping the filaments together by twisting them or entangling themor both. As with staple yarns, multiple strands can be plied together toform a thicker yarn.

Once formed, the yarn can undergo further treatment such as texturizing,thermal or mechanical treating, or coating with a material such as asynthetic polymer. The fibers, yarns, or textiles, or any combinationthereof, used in the disclosed articles can be sized. Sized fibers,yarns, and/or textiles are coated on at least part of their surface witha sizing composition selected to change the absorption or wearcharacteristics, or for compatibility with other materials. The sizingcomposition facilitates wet-out and wet-through of the coating or resinupon the surface and assists in attaining desired physical properties inthe final article. An exemplary sizing composition can comprise, forexample, epoxy polymers, urethane-modified epoxy polymers, polyesterpolymers, phenol polymers, polyamide polymers, polyurethane polymers,polycarbonate polymers, polyetherimide polymers, polyamideimidepolymers, polystylylpyridine polymers, polyimide polymers bismaleimidepolymers, polysulfone polymers, polyethersulfone polymers,epoxy-modified urethane polymers, polyvinyl alcohol polymers, polyvinylpyrrolidone polymers, and mixtures thereof.

Two or more yarns can be combined, for example, to form composite yarnssuch as single- or double-covered yarns, and corespun yarns.Accordingly, yarns may have a variety of configurations that generallyconform to the descriptions provided herein.

The yarn can comprise at least one thermoplastic material (e.g., one ormore of the fibers can be made of thermoplastic material). The yarn canbe made of a thermoplastic material. The yarn can be coated with a layerof a material such as a thermoplastic material.

The linear mass density or weight per unit length of a yarn can beexpressed using various units, including denier (D) and tex. Denier isthe mass in grams of 9000 meters of yarn. The linear mass density of asingle filament of a fiber can also be expressed using denier perfilament (DPF). Tex is the mass in grams of a 1000 meters of yarn.Decitex is another measure of linear mass, and is the mass in grams fora 10,000 meters of yarn.

As used herein, tenacity is understood to refer to the amount of force(expressed in units of weight, for example: pounds, grams, centinewtonsor other units) needed to break a yarn (i.e., the breaking force orbreaking point of the yarn), divided by the linear mass density of theyarn expressed, for example, in (unstrained) denier, decitex, or someother measure of weight per unit length. The breaking force of the yarnis determined by subjecting a sample of the yarn to a known amount offorce, for example, using a strain gauge load cell such as an INSTRONbrand testing system (Norwood, Mass., USA). Yarn tenacity and yarnbreaking force are distinct from burst strength or bursting strength ofa textile, which is a measure of how much pressure can be applied to thesurface of a textile before the surface bursts.

Generally, in order for a yarn to withstand the forces applied in anindustrial knitting machine, the minimum tenacity required isapproximately 1.5 grams per Denier. Most yarns formed from commoditypolymeric materials generally have tenacities in the range of about 1.5grams per Denier to about 4 grams per Denier. For example, polyesteryarns commonly used in the manufacture of knit uppers for footwear havetenacities in the range of about 2.5 to about 4 grams per Denier. Yarnsformed from commodity polymeric materials which are considered to havehigh tenacities generally have tenacities in the range of about 5 gramsper Denier to about 10 grams per Denier. For example, commerciallyavailable package dyed polyethylene terephthalate yarn from NationalSpinning (Washington, N.C., USA) has a tenacity of about 6 grams perDenier, and commercially available solution dyed polyethyleneterephthalate yarn from Far Eastern New Century (Taipei, Taiwan) has atenacity of about 7 grams per Denier. Yarns formed from high performancepolymeric materials generally have tenacities of about 11 grams perDenier or greater. For example, yarns formed of aramid fiber typicallyhave tenacities of about 20 grams per Denier, and yarns formed ofultra-high molecular weight polyethylene (UHMWPE) having tenacitiesgreater than 30 grams per Denier are available from Dyneema (Stanley,N.C., USA) and Spectra (Honeywell-Spectra, Colonial Heights, Va., USA).

Various techniques exist for mechanically manipulating yarns to form atextile. Such techniques include, for example, interweaving,intertwining and twisting, and interlooping. Interweaving is theintersection of two yarns that cross and interweave at right angles toeach other. The yarns utilized in interweaving are conventionallyreferred to as “warp” and “weft.” A woven textile includes include awarp yarn and a weft yarn. The warp yarn extends in a first direction,and the weft strand extends in a second direction that is substantiallyperpendicular to the first direction. Intertwining and twistingencompasses various procedures, such as braiding and knotting, whereyarns intertwine with each other to form a textile. Interloopinginvolves the formation of a plurality of columns of intermeshed loops,with knitting being the most common method of interlooping. The textilemay be primarily formed from one or more yarns that aremechanically-manipulated, for example, through interweaving,intertwining and twisting, and/or interlooping processes, as mentionedabove.

The textile can be a nonwoven textile. Generally, a nonwoven textile orfabric is a sheet or web structure made from fibers and/or yarns thatare bonded together. The bond can be a chemical and/or mechanical bond,and can be formed using heat, solvent, adhesive or a combinationthereof. Exemplary nonwoven fabrics are flat or tufted porous sheetsthat are made directly from separate fibers, molten plastic and/orplastic film. They are not made by weaving or knitting and do notnecessarily require converting the fibers to yarn, although yarns can beused as a source of the fibers. Nonwoven textiles are typicallymanufactured by putting small fibers together in the form of a sheet orweb (similar to paper on a paper machine), and then binding them eithermechanically (as in the case of felt, by interlocking them with serratedor barbed needles, or hydro-entanglement such that the inter-fiberfriction results in a stronger fabric), with an adhesive, or thermally(by applying binder (in the form of powder, paste, or polymer melt) andmelting the binder onto the web by increasing temperature). A nonwoventextile can be made from staple fibers (e.g., from wetlaid, airlaid,carding/crosslapping processes), or extruded fibers (e.g., frommeltblown or spunbond processes, or a combination thereof), or acombination thereof. Bonding of the fibers in the nonwoven textile canbe achieved with thermal bonding (with or without calendering),hydro-entanglement, ultrasonic bonding, needlepunching (needlefelting),chemical bonding (e.g., using binders such as latex emulsions orsolution polymers or binder fibers or powders), meltblown bonding (e.g.,fiber is bonded as air attenuated fibers intertangle during simultaneousfiber and web formation).

Now having described various aspects of the present disclosure,additional discussion is provided regarding when the optical element isused in conjunction with a bladder. The bladder can be unfilled,partially inflated, or fully inflated when the optical element isdisposed onto the bladder. The bladder is a bladder capable of includinga volume of a fluid. An unfilled bladder is a fluid-fillable bladder anda filled bladder that has been at least partially inflated with a fluidat a pressure equal to or greater than atmospheric pressure. Whendisposed onto or incorporated into an article of footwear, apparel, orsports equipment, the bladder is generally, at that point, afluid-filled bladder. The fluid be a gas or a liquid. The gas caninclude air, nitrogen gas (N₂), or other appropriate gas.

The bladder can have a gas transmission rate for nitrogen gas, forexample, where a bladder wall of a given thickness has a gastransmission rate for nitrogen that is at least about ten times lowerthan the gas transmission rate for nitrogen of a butyl rubber layer ofsubstantially the same thickness as the thickness of the bladderdescribed herein. The bladder can have a first bladder wall having afirst bladder wall thickness (e.g., about 0.1 to 40 mils). The bladdercan have a first bladder wall that can have a gas transmission rate(GTR) for nitrogen gas of less than about 15 cm³/m²·atm·day, less thanabout 10 m³/m²·atm·day, less than about 5 cm³/m²·atm·day, less thanabout 1 cm³/m²·atm·day (e.g., from about 0.001 cm³/m²·atm·day to about 1cm³/m²·atm·day, about 0.01 cm³/m²·atm·day to about 1 cm³/m²·atm·day orabout 0.1 cm³/m²·atm·day to about 1 cm³/m²·atm·day) for an average wallthickness of 20 mils. The bladder can have a first bladder wall having afirst bladder wall thickness, where the first bladder wall has a gastransmission rate of 15 cm³/m²·atm·day or less for nitrogen for anaverage wall thickness of 20 mils.

In an aspect, the bladder has a bladder wall having an interior-facingside and an exterior (or externally)-facing side, where the interior (orinternally)-facing side defines at least a portion of an interior regionof the bladder. The optical element having a first side and a secondopposing side can be disposed on the exterior-facing side of thebladder, the interior-facing side of the bladder, or both. The opticalelement can be disposed in-line or on its side. Where the opticalelement is disposed on its side, the optical element is disposed on theinterior-facing side or the exterior-facing side on its sideconfiguration as opposed to in line configuration.

The exterior-facing side of the bladder, the interior-facing side of thebladder, or both can optionally include a plurality of topographicalstructures (or profile features) extending from the exterior-facing sideof the bladder wall, the interior-facing side of the bladder, or both,where the first side or the second side of the optical element isdisposed on the exterior-facing side of the bladder wall and coveringthe plurality of topographical structures, the interior-facing side ofthe bladder wall and covering the plurality of topographical structures,or both, and wherein the optical element imparts a structural color tothe bladder wall.

In a particular aspect, the bladder can include a top wall operablysecured to the footwear upper, a bottom wall opposite the top wall, andone or more sidewalls extending between the top wall and the bottom wallof the inflated bladder. The top wall, the bottom wall, and the one ormore sidewalls collectively define an interior region of the inflatedbladder, and wherein the one or more sidewalls each comprise anexterior-facing side. The optical element having a first side and asecond opposing side can be disposed on the exterior-facing side of thebladder, the interior-facing side of the bladder, or both. Optionally,the exterior-facing side of the bladder, the interior-facing side of thebladder, or both can include a plurality of topographical structuresextending from the exterior-facing side of the bladder wall, theinterior-facing side of the bladder, or both, where the first side orthe second side of the optical element is disposed on theexterior-facing side of the bladder wall and covering the plurality oftopographical structures, the interior-facing side of the bladder walland covering the plurality of topographical structures, or both, andwherein the optical element imparts a structural color to the bladderwall.

An accepted method for measuring the relative permeance, permeability,and diffusion of inflated bladders is ASTM D-1434-82-V. See, e.g., U.S.Pat. No. 6,127,026, which is incorporated by reference as if fully setforth herein. According to ASTM D-1434-82-V, permeance, permeability anddiffusion are measured by the following formulae:

Permeance

(quantity of gas)/[(area)×(time)×(pressure difference)]=permeance(GTR)/(pressure difference)=cm³/m²·atm·day (i.e., 24 hours)

Permeability

[(quantity of gas)×(film thickness)][(area)×(time)×(pressuredifference)]=permeability [(GTR)×(film thickness)]/(pressuredifference)=[(cm³)(mil)]/m²·atm·day (i.e., 24 hours)

Diffusion at One Atmosphere

(quantity of gas)/[(area)×(time)]=GTR=cm³/m²·day (i.e., 24 hours)

The bladder can include a bladder wall that includes a film including atleast one polymeric layer or at least two or more polymeric layers. Eachof the polymeric layers can be about 0.1 to 40 mils in thickness.

The polymeric layer can be formed of polymer material such as athermoplastic material as described above and herein and can be thethermoplastic layer upon which the optical element can be disposed andoptionally upon which the textured layer can be disposed or thethermoplastic layer can be used to form the textured layer, and thelike. The thermoplastic material can include an elastomeric material,such as a thermoplastic elastomeric material. The thermoplasticmaterials can include thermoplastic polyurethane (TPU), such as thosedescribed above and herein. The thermoplastic materials can includepolyester-based TPU, polyether-based TPU, polycaprolactone-based TPU,polycarbonate-based TPU, polysiloxane-based TPU, or combinationsthereof. Non-limiting examples of thermoplastic material that can beused include: “PELLETHANE” 2355-85ATP and 2355-95AE (Dow ChemicalCompany of Midland, Mich., USA), “ELASTOLLAN” (BASF Corporation,Wyandotte, Mich., USA) and “ESTANE” (Lubrizol, Brecksville, Ohio, USA),all of which are either ester or ether based. Additional thermoplasticmaterial can include those described in U.S. Pat. Nos. 5,713,141;5,952,065; 6,082,025; 6,127,026; 6,013,340; 6,203,868; and 6,321,465,which are incorporated herein by reference.

The polymeric layer can be formed of one or more of the following:ethylene-vinyl alcohol copolymers (EVOH), poly(vinyl chloride),polyvinylidene polymers and copolymers (e.g., polyvinylidene chloride),polyamides (e.g., amorphous polyamides), acrylonitrile polymers (e.g.,acrylonitrile-methyl acrylate copolymers), polyurethane engineeringplastics, polymethylpentene resins, ethylene-carbon monoxide copolymers,liquid crystal polymers, polyethylene terephthalate, polyether imides,polyacrylic imides, and other polymeric materials known to haverelatively low gas transmission rates. Blends and alloys of thesematerials as well as with the TPUs described herein and optionallyincluding combinations of polyimides and crystalline polymers, are alsosuitable. For instance, blends of polyimides and liquid crystalpolymers, blends of polyamides and polyethylene terephthalate, andblends of polyamides with styrenics are suitable.

Specific examples of polymeric materials of the polymeric layer caninclude acrylonitrile copolymers such as “BAREX” resins, available fromIneos (Rolle, Switzerland); polyurethane engineering plastics such as“ISPLAST” ETPU available from Lubrizol (Brecksville, Ohio, USA);ethylene-vinyl alcohol copolymers marketed under the tradenames “EVAL”by Kuraray (Houston, Tex., USA), “SOARNOL” by Nippon Gohsei (Hull,England), and “SELAR OH” by DuPont (Wilmington, Del., USA);polyvinylidiene chloride available from S.C. Johnson (Racine, Wis., USA)under the tradename “SARAN”, and from Solvay (Brussels, Belgium) underthe tradename “IXAN”; liquid crystal polymers such as “VECTRA” fromCelanese (Irving, Tex., USA) and “XYDAR” from Solvay; “MDX6” nylon, andamorphous nylons such as “NOVAMID” X21 from Koninklijke DSM N.V(Heerlen, Netherlands), “SELAR PA” from DuPont; polyetherimides soldunder the tradename “ULTEM” by SABIC (Riyadh, Saudi Arabia); poly(vinylalcohol)s; and polymethylpentene resins available from Mitsui Chemicals(Tokyo, Japan) under the tradename “TPX”.

Each polymeric layer of the film can be formed of a thermoplasticmaterial which can include a combination of thermoplastic polymers. Inaddition to one or more thermoplastic polymers, the thermoplasticmaterial can optionally include a colorant, a filler, a processing aid,a free radical scavenger, an ultraviolet light absorber, and the like.Each polymeric layer of the film can be made of a different ofthermoplastic material including a different type of thermoplasticpolymer.

The bladder can be made by applying heat, pressure and/or vacuum to afilm. In this regard, the optical element and optionally the texturedlayer, and the like can be disposed, formed from, or the like prior to,during, and/or after these steps. The bladder (e.g., one or morepolymeric layers) can be formed using one or more polymeric materials,and forming the bladder using one or more processing techniquesincluding, for example, extrusion, blow molding, injection molding,vacuum molding, rotary molding, transfer molding, pressure forming, heatsealing, casting, low-pressure casting, spin casting, reaction injectionmolding, radio frequency (RF) welding, and the like. The bladder can bemade by co-extrusion followed by heat sealing or welding to give aninflatable bladder, which can optionally include one or more valves(e.g., one way valves) that allows the bladder to be filled with thefluid (e.g., gas).

Now having described the optical element, the optional textured surface,and methods of making the article are now described. In an aspect, themethod includes forming layers using one or more techniques describedherein. In an aspect, the method includes forming the optical element ina layer-by-layer manner on a surface of an article such as a textile,film, fiber, or monofilament yarn, where the surface can optionally bethe textured surface. Another embodiment of the present disclosureincludes disposing the optical element on the substrate.

The method provides for the layers of the optical element being formedon the textured surface. Alternatively, the textured surface can beformed in/on the layer adjacent the surface of the article, and then theremaining layers are disposed thereon. As described herein, the opticalelement can be formed in a layer-by-layer manner, where each layer has adifferent index of refraction. As each layer is formed the undulationsand flat regions are altered. The combination of the optional texturedsurface (e.g., dimensions, shape, and/or spacing of the profileelements) and the layers of the optical element (e.g., number of layers,thickness of layers, material of the layers) and the resultantundulations and planar areas impart the structural color when exposed tovisible light. The method includes optionally forming a protective layerover the optical element to protect the optical element. Each layer ofthe optical element can be formed in turn, where each layer can beformed then after an appropriate amount of time, additional processing,cooling, or the like, the next layer of the optical element can beformed.

Measurements for visible light transmittance and visible lightreflectance were performed using a Shimadzu UV-2600 Spectrometer(Shimadzu Corporation, Japan). The spectrometer was calibrated using astandard prior to the measurements. The incident angle for allmeasurements was zero.

The visible light transmittance was the measurement of visible light (orlight energy) that was transmitted through a sample material whenvisible light within the spectral range of 300 nanometers to 800nanometers was directed through the material. The results of alltransmittance over the range of 300 nanometers to 800 nanometers wascollected and recorded. For each sample, a minimum value for the visiblelight transmittance was determined for this range.

The visible light reflectance was a measurement of the visible light (orlight energy) that was reflected by a sample material when visible lightwithin the spectral range of 300 nanometers to 800 nanometers wasdirected through the material. The results of all reflectance over therange of 300 nanometers to 800 nanometers was collected and recorded.For each sample, a minimum value for the visible light reflectance wasdetermined for this range.

It should be emphasized that the above-described aspects of the presentdisclosure are merely possible examples of implementations, and are setforth only for a clear understanding of the principles of thedisclosure. Many variations and modifications may be made to theabove-described aspects of the disclosure without departingsubstantially from the spirit and principles of the disclosure. All suchmodifications and variations are intended to be included herein withinthe scope of this disclosure.

It should be noted that ratios, concentrations, amounts, and othernumerical data may be expressed herein in a range format. It is to beunderstood that such a range format is used for convenience and brevity,and thus, should be interpreted in a flexible manner to include not onlythe numerical values explicitly recited as the limits of the range, butalso to include all the individual numerical values or sub-rangesencompassed within that range as if each numerical value and sub-rangeis explicitly recited. To illustrate, a concentration range of “about0.1 percent to about 5 percent” should be interpreted to include notonly the explicitly recited concentration of about 0.1 weight percent toabout 5 weight percent but also include individual concentrations (e.g.,1 percent, 2 percent, 3 percent, and 4 percent) and the sub-ranges(e.g., 0.5 percent, 1.1 percent, 2.2 percent, 3.3 percent, and 4.4percent) within the indicated range. The term “about” can includetraditional rounding according to significant figures of the numericalvalue. In addition, the phrase “about ‘x’ to ‘y’” includes “about ‘x’ toabout ‘y’”.

The term “providing”, such as for “providing an article” and the like,when recited in the claims, is not intended to require any particulardelivery or receipt of the provided item. Rather, the term “providing”is merely used to recite items that will be referred to in subsequentelements of the claim(s), for purposes of clarity and ease ofreadability.

Many variations and modifications may be made to the above-describedaspects. All such modifications and variations are intended to beincluded herein within the scope of this disclosure and protected by thefollowing claims.

We claim:
 1. An article comprising: an optical element disposed on asurface of the article, wherein the optical element includes at least afirst section disposed on a first area of the article and a secondsection disposed on a second area of the article, wherein the firstsection of the optical element imparts a first structural color to thefirst area of the article, wherein the second section of the opticalelement imparts a second structural color to the second area of thearticle, and wherein the first structural color and the secondstructural color are different when viewed from the same angle ofobservation of a viewer having 20/20 visual acuity and normal colorvision from a distance of about 1 meter from the article; wherein theoptical element comprises at least one layer, wherein the first sectionhas a first number of layers and the second section has a second numberof layers, wherein the first number of layers and the second number oflayer are different, wherein at least the first layer for each of thefirst section and the second section are made of the same material. 2.The article of claim 1, wherein the first section has a first layerhaving a first section first layer thickness and the second section hasa first layer having a second section first layer thickness, wherein thefirst section first layer thickness and the second section first layerthickness are the same
 3. The article of claim 2, wherein at least thesecond layer for each of the first section and the second sectiondisposed on the first layer have the same thickness.
 4. The article ofclaim 3, wherein the first layer of the first section of the opticalelement and the first layer of the second section of the optical elementform a first contiguous layer which extends over the first section ofthe optical element and the second section of the optical element. 5.The article of claim 4, wherein each layer of the second section andeach corresponding layer in the first section each independently form acontiguous layer that which extends over the first section of theoptical element and the second section of the optical element.
 6. Thearticle of claim 5, wherein the first contiguous layer consistsessentially of the same material.
 7. The article of claim 5, whereineach contiguous layer independently consists essentially of the samematerial.
 8. The article of claim 1, wherein the first section includesa first set of layers, wherein the second section includes a second setof layers, wherein the first set of layers includes at least one morelayer than the second set of layers, wherein the material of each layerof the first set of layers corresponds to the material of each layer ofthe second set of layers, and wherein each of the layers of the secondsection have the same thickness of the corresponding layers in the firstsection.
 9. The article of claim 1, wherein the first section includes afirst set of layers, wherein the second section includes a second set oflayers, wherein the index of refraction of each corresponding layer ofthe first set of layers corresponds to the index of refraction of eachcorresponding layer of the second set of layers.
 10. The article ofclaim 9, wherein vertically adjacent layers of the second section havedifferent index of refractions, wherein vertically adjacent layers ofthe first section have different index of refractions.
 11. The articleof claim 9, wherein the index of refraction of each layer of the firstset of layers is different, wherein the index of refraction of eachlayer of the second set of layers is different.
 12. The article of claim1, wherein the second set of layers has at least one 2 layers less thanthe first set layers.
 13. The article of claim 1, wherein the surface ofthe article is a flat or a substantially flat surface.
 14. The articleof claim 1, wherein when measured according to the CIE 1976 color spaceunder a given illumination condition at a first observation angle ofabout −15 to 180 degrees or about or about −15 degrees and +60 degrees,the optical element has a first color measurement having coordinates L₁*and a₁* and b₁* as measured from the first section of the opticalelement, and optical element has a second color measurement havingcoordinates L₂* and a₂* and b₂* as measured from the second section ofthe optical element, whereΔE*_(ab)=[(L₁*−L₂*)²+(a₁*−a₂*)²+(b₁*−b₂*)²]^(1/2), wherein the ΔE*_(ab)between the first color measurement and the second color measurement isgreater than about 3, then the first structural color and the secondstructural color are different.
 15. The article of claim 1, wherein thefirst section of the optical element has 2 to 10 layers and wherein thesecond section has 1 to 9 layers.
 16. The article of claim 15, eachlayer has a thickness of about 10 nanometers to about 50 nanometers. 17.The article of claim 1, wherein the first section of the optical elementhas a first section average thickness of about 40 to about 100nanometers and the second section of the of the optical element has asecond section average thickness of about 20 to 80 nanometers.
 18. Thearticle of claim 1, further comprising a third section disposed on athird area of the article, wherein the third section of the opticalelement imparts a third structural color to the third area of thearticle, and wherein a color parameter of the first structural color,the second structural color, and the third structural color aredifferent when viewed from the same angle of observation of a viewerhaving 20/20 visual acuity and normal color vision from a distance ofabout 1 meter from the article; wherein the third section has a thirdnumber of layers, wherein the first number of layers, the second numberof layers, and the third number of layers are different, wherein atleast the first layer for each of the first section, the second section,and the third section are made of the same material, wherein each of thelayers of the third section have the same thickness of the correspondinglayers in the first section.
 19. A method of making an article,comprising: disposing the optical element of claim 1 onto the surface ofthe article.
 20. An article comprising: a product of the method of claim19.